School Readiness, Learning Challenges, and Lifestyle Changes Among Children During the COVID‐19 Pandemic

ABSTRACT

Background

The COVID‐19 pandemic disrupted schooling worldwide. While there is evidence of declines in academic performance, the links between early vulnerabilities in school readiness, learning difficulties, and lifestyle changes during the pandemic and their impact on postcrisis academic achievement are not well understood.

Methods

This longitudinal study followed 3871 children across three time points over 6 years (50.3% boys). In 2017, teachers assessed children's school readiness at kindergarten. In 2021, parents assessed the impact of COVID‐19 on their child's learning difficulties and lifestyle changes. In 2022, teachers assessed children's academic achievement.

Results

Structural equation modeling showed that children with school readiness vulnerabilities experienced greater learning difficulties during the pandemic, but not significantly greater lifestyle disruptions. Learning difficulties partially mediated the association between school readiness vulnerabilities and lower postcrisis academic achievement. Analyses were adjusted for child sex, age, native language, and cumulative socioeconomic risk.

Implications for School Health Policy, Practice, and Equity

Support systems should monitor learning difficulties that emerge during periods of educational disruption and not rely solely on preexisting indicators of vulnerability.

Conclusion

Learning difficulties during the pandemic emerged as a distinct predictor of later academic achievement, emphasizing the need for timely educational support during periods of disruption.

1. Introduction

Over the course of the first 2 years of the COVID‐19 pandemic, the province of Quebec in Canada underwent four lockdowns, corresponding to the four major waves of the virus. The population was under significant restrictions for 15 months, including the closure of nonessential businesses and the banning of most indoor gatherings. Major events were canceled, social outings, trips, and activities were prohibited, and schools were fully remote for a total of 145 days [1]. School closures during this period are estimated to have affected approximately 1.5 billion students worldwide [2]. At that time, many children faced disengagement, a decline in academic performance, and disruption to their routines, whereas teachers struggled to adopt online solutions [3].

1.1. Learning Difficulties During the Pandemic

Learning difficulties were a challenge for many children during the pandemic. The term learning difficulties is used here in a nonclinical sense to refer to variation in learning performance within the typical range and does not denote diagnosed conditions such as intellectual disabilities. A study in the Netherlands [4] (n = 350,000; aged 8–11) evaluated the effect of school lockdowns on children's performance on core subjects (math, spelling, and reading). The study reported that children made little to no progress while learning from home. Learning stagnation or loss was most pronounced among students from disadvantaged homes [5, 6, 7]. Similarly, a recent study [8] conducted with 23,986 students in the province of Quebec, Canada, used the same ministerial reading test to compare two cohorts before and after the pandemic. They found that students in the lowest decile of performance lost more (e.g., a drop of 20 percentage points), followed by a moderate loss for those in the middle decile (e.g., a drop of 10 percentage points) and no losses for students in the highest decile of performance. This suggests that students who were struggling academically before the pandemic were more likely to fall further behind afterwards.

1.2. Children's Lifestyle During Pandemic

Learning was not the only thing impacted by the pandemic; children's lifestyles have also been affected. Studies observed an increase in sedentary behaviors, greater screen time, more sleep time but of lesser quality, fewer interactions with friends, and some mixed evidence regarding changes in nutrition [9, 10, 11, 12]. In a Canadian sample, the proportion of youth meeting Canada's physical activity recommendations of 60 min of moderate physical activity per day dropped by 14.8% and 9.9% among boys and girls, respectively, between 2018 and fall of 2020 [13]. The proportion returned to pre‐pandemic levels by the fall of 2021 for boys, but not for girls. A systematic review [14] across countries (N = 86,981) observed that 64 studies out of 66 reported a decrease in physical activity during their respective lockdowns. This drastic change in routine is likely to have impacted children's school motivation and their ability to learn [15]. However, the association between lifestyle changes and learning difficulties during the pandemic remains under‐researched, particularly among vulnerable groups.

1.3. Vulnerability in School Readiness

In kindergarten, children who develop their motor, affective, social, language, and cognitive skills at a slower pace than their peers are considered to exhibit vulnerabilities in school readiness. This vulnerability can hinder their ability to fully benefit from school learning opportunities and social interactions.

These children are at increased risk during periods of disruption such as physical distancing, school closures, and activity cancellations. This heightened risk reflects both their need for additional developmental support and their greater exposure to household precarity, stressful family environments, parental health challenges, and lower parental education levels [3, 16]. Evidence suggests that proximal processes, particularly parent–child interactions and parental involvement in learning, play a central role in early development [17]. These family‐level processes become especially salient during periods such as lockdowns, when children spend increased time at home.

Studies have reported decreases in healthy lifestyle behaviors among children during COVID‐19 [18, 19]. However, little is known about how lifestyle changes and learning difficulties during the pandemic were experienced by children with school readiness vulnerabilities and how these factors relate to later academic achievement. Addressing this gap is important for understanding mechanisms of risk and resilience in child development under stress.

From an applied perspective, identifying whether lifestyle changes are associated with learning difficulties could inform targeted school and community interventions (e.g., structured extracurricular activities, and sleep hygiene support) aimed at mitigating the longer‐term academic consequences of disruption.

1.4. This Study

The primary aim of this study was to examine whether preexisting vulnerabilities in school readiness at kindergarten (in 2017) were associated with learning difficulties during the COVID‐19 pandemic (2020–2021), lifestyle changes during the pandemic, and academic achievement 2 years later (2022).

A secondary aim was to assess how learning difficulties and lifestyle changes during the pandemic related to subsequent academic achievement. We hypothesized that vulnerabilities in school readiness would predict greater learning difficulties, more negative lifestyle changes, and lower academic achievement. We further hypothesized that learning difficulties and lifestyle changes would mediate the relationship between vulnerabilities in school readiness and academic achievement.

2. Methods

2.1. Data Collection

Data collection was carried out in three phases, as shown in Figure 1. More details can be found in Data S1.

FIGURE 1.

The three phases of the Quebec Resilience project based on school closures to prevent the spread of COVID‐19.

2.2. Participants

The total sample consisted of n = 3871 children who participated in all three phases of the project. 50.3% were boys with an average age of 11 years at the third time of the data collection. In Phase I, n ≈ 5000 teachers assessed the school readiness of 83,335 children attending kindergarten. In Phase II, n = 4524 parents (77% mothers, 22% fathers, and < 1% legal guardians) completed a series of questionnaires to understand the impact of the COVID‐19 pandemic on their children. Finally, in Phase III, n = 3661 teachers assessed a total of 8217 children from their classes between March and June 2022. All assessments were conducted by the children's classroom teachers or parents.

Sampling weights were estimated by the Institut de la statistique du Québec (ISQ) to allow our analytical sample to be representative of the Quebec population of children originally surveyed in Phase I. More information is available in Data S1 Section Data Collection.

2.3. Measures

This study was part of a larger data collection initiative that included additional measures not analyzed in the present study.

2.3.1. Pre‐Pandemic Variable, Assessed by Teachers in 2017

Vulnerability in school readiness: The presence of a vulnerability in school readiness was evaluated when participants were in kindergarten at 6 years old (in 2017). We used the Early Development Instrument (EDI; McMaster University, Offord Centre for Child Studies [20, 21]). This questionnaire was answered by teachers. It covers five domains of development: physical health and well‐being, social skills, emotional maturity, language and cognitive development, and communication skills and general knowledge. A score ranging from 0 to 10 was calculated for each domain. Children scoring below the 10th percentile of the distribution of a normative sample in at least one domain were categorized as “vulnerable” [22]. A validation study of the EDI suggested good convergent validity toward direct assessments of phonological awareness and early social competence [20]. The convergent validity of the overall EDI scores has been supported, while its discriminant validity suggested that a single score had greater validity than one score per domain.

2.3.2. Pandemic Variables (Assessed From July to September 2021)

Children learning difficulties during the pandemic: Parents rated the severity of their child's learning difficulties during the 2020–2021 school year using a 5‐point Likert‐type scale ranging from “None” to “Very important.” The following item was used: “In general, to what extent do you consider that the child has had difficulties in learning at school during the year 2020–2021?” The measure was not specific to a school subject.

Children's lifestyle changes: The research team designed a questionnaire with contributions from a diverse group of advisers, comprising experts in pediatrics, education, social sciences, and public health. Children's lifestyle changes due to the pandemic were assessed by their parents. The scale captured eight domains: (1) mental health, (2) sleep habits, (3) nutrition habits, (4) physical activity, (5) screen usage (television, cell phone, tablet, video game console, etc.), (6) school motivation, (7) relationships with friends, and (8) relationships with siblings. The answers were anchored on a 5‐point scale with higher scores indicating positive changes (1 = very negative to 5 = very positive). An example item was “Impact of the COVID‐19 pandemic on… their school motivation.” We estimated a latent variable called Lifestyle Changes which encompasses all eight domains of life and thus corresponds to an overall positive lifestyle change.

2.3.3. Two Years After the Onset of the Pandemic (Assessed in June 2022)

Children academic achievement: Fifth‐grade teachers evaluated children's academic achievement relative to the educational program's expectations in eight subject areas: (1) writing, (2) reading, (3) oral communication, (4) mathematical problem‐solving, (5) mathematical reasoning, (6) geography, history and citizenship education, (7) science and technology, and (8) second language. The answers were anchored on a 5‐point scale (1—far below program expectations to 5—far above program expectations). We estimated a latent variable called Academic Achievement which corresponds to children's ability to meet the program expectations in all eight subjects.

2.4. Covariates

We controlled for child's sex, age, native language (French or English vs. other), and a cumulative socioeconomic risk index, as these factors are predictors of academic achievement [23].

Cumulative socioeconomic risk index: A cumulative socioeconomic risk index was calculated by summing three binary indicators of socioeconomic status, including (a) parents' educational level (1 = a professional diploma/certificate or lower), (b) single‐parent household (1 = single parent), and (c) low‐income household (1 = below the poverty line). The poverty line cut‐off was calculated based on the total revenue of the household before taxes and adjusted for the number of occupants in the house, as assessed during the second phase of data collection, in 2021. The reference threshold corresponds to half the median household income for individuals of all ages.

2.5. Plan of Analyses

First, we compared the characteristics of vulnerable and non‐vulnerable children on their lifestyle changes, learning difficulties, and academic achievement. Second, we estimated a structural equation model (SEM) and a mediation analysis. The use of latent variables helps to assess psychological constructs more accurately by combining multiple imperfect indicators. We used conventional goodness‐of‐fit indicators and thresholds to assess the fit of the latent constructs before fitting the structural model (i.e., χ ² closer to zero, BIC closer to zero, RMSEA < 0.10, CFI > 0.90, TLI > 0.90, SRMR < 0.05, primary loadings > 0.40 [24]; but see Marsh et al. [25] for a critique of relying solely on fit indicators). The mediation model tested the association between vulnerability in school readiness and later academic achievement explained by lifestyle changes and learning difficulties during the pandemic.

All analyses were conducted in Mplus, version 8, with full information maximum likelihood to handle missing data and maximum likelihood robust estimation to handle deviations from a normal distribution [26]. A statistical significance threshold was set at an error rate of α = 1% due to the large sample size. Missing data accounted for 2.6% across all variables. The significance of the indirect effects of the mediations was estimated with bias‐corrected bootstrap and 1000 resamples.

3. Results

Children's characteristics according to the presence or absence of a vulnerability in school readiness are reported in Table 1. Notably, there were proportionally more boys with a vulnerability in school readiness (65.5%) compared to girls (34.5%) and more children with a vulnerability in school readiness scoring higher on the cumulative risk index (24% vs. 13.9%).

TABLE 1.

Characteristics of the participants according to the presence of a vulnerability in kindergarten.

	Total weighted (N a  = 83,335)	With a vulnerability in school readiness (n = 20,643)	Without a vulnerability (n = 62,691)
Child age (years), M (SD)	11.11 (0.04)	11.08 (0.05)	11.13 (0.04)
Child sex, N (%)
Boy	41,917 (50.3%)	13,521 (65.5%)	28,336 (45.2%)
Girl	41,417 (49.7%)	7121 (34.5%)	34,341 (54.8%)
Child maternal language, N (%)
French or English	68,501 (82.2%)	15,915 (77.1%)	52,597 (83.9%)
Other	14,833 (17.8%)	4727 (22.9%)	10,093 (16.1%)
Cumulative risk index, N (%)
0	35,584 (42.7%)	6729 (32.6%)	28,837 (46.0%)
1	34,167 (41.0%)	8979 (43.5%)	25,139 (40.1%)
2	10,000 (12.0%)	3447 (16.7%)	6519 (10.4%)
3	3666 (4.4%)	1506 (7.3%)	2194 (3.5%)
During pandemic (2020–2021)
Child learning difficulties during‐pandemic, N (%)
No difficulties	32,250 (38.7%)	4541 (22.0%)	27,709 (44.2%)
Minor difficulties	37,667 (45.2%)	10,292 (49.8%)	27,385 (43.7%)
Important difficulties	11,166 (13.4%)	4562 (22.1%)	6582 (10.5%)
Very important difficulties	2250 (2.7%)	1259 (6.1%)	1003 (1.6%)
Child lifestyle changes (M, SD) (from 1—very negative to 5—very positive)	2.59 (0.07)	2.60 (0.08)	2.59 (0.06)
2‐year after the onset (2022)
Child academic achievement (M, SD) (from 1—far below program expectations to 5—far above program expectations)	3.48 (0.13)	2.98 (0.14)	3.64 (0.12)

Abbreviation: SD, standard deviation.

^a Descriptive statistics are weighted to represent the target population (≈83,335 children); unweighted sample size is n = 3871 (see Section 2.2).

Source: Data compiled from the file of Résilience Parents (2023), Gouvernement du Québec, Institut de la statistique du Québec.

Lifestyle changes across vulnerable and non‐vulnerable children are shown in Figures 2 and 3. Detailed numbers are reported in Table S1. The difference between children with and without a vulnerability was minimal in most domains (∆mean difference = 0.01; see Table 1). Overall, according to parents, children with and without a vulnerability all manifested increased screen time, less physical activity, less school motivation, less relationship with friends, and lower mental health. About 15% of parents noted adverse effects on their child's sleep, nutrition, and relationships with siblings, yet the majority—around 75%—reported no impact on those domains. Positive effects were more likely to be reported for relationships with friends and siblings.

FIGURE 2.

Proportion of parents reporting negative effects of pandemic disruptions on their child. Panel A: Vulnerable children. Panel B: Non‐vulnerable children. Correspond to the answers “somewhat negative” and “very negative” impacts of the pandemic on each domain.

FIGURE 3.

Proportion of parents reporting positive effects of pandemic disruptions on their child's. Panel A: Vulnerable children. Panel B: Non‐vulnerable children. Correspond to the answers “somewhat positive” and “very positive” impact of the pandemic on each domain.

Children with a vulnerability in school readiness had lower academic achievement postcrisis (averaged across eight academic subjects) compared to children without a vulnerability (respective means = 2.98, SD = 0.97 vs. mean = 3.64, SD = 0.80, Cohen's d = 0.74), where a score of three suggests that expectations are met. This indicates that children with a vulnerability are just meeting the program's expectations on average, whereas children without a vulnerability tend to surpass the program's expectations.

3.1. Latent Constructs Measurement Models

We used latent variables to combine the indicators of lifestyle changes and academic achievement into two latent constructs, respectively. The fit of CFA models with and without post hoc modifications is reported in Table S2. More information on the specification process of the latent constructs is also available in Data S1.

For the latent Lifestyle changes construct, a single latent factor with correlated residuals between the items “physical activity” and “screen usage,” as well as between “sleep,” “health,” and “nutrition,” was a satisfactory model (χ ² = 146**, RMSEA = 0.04 [0.04, 0.05], CFI = 0.96, TLI = 0.94, SRMR = 0.03). This model was carried over into the final SEM. The reliability coefficient of the eight items was α = 0.81.

For the latent Academic achievement construct, a single latent factor with correlated residuals between “reading” and “writing,” as well as between “mathematical problem‐solving” and “mathematical reasoning” was a satisfying model (χ ² = 378**, RMSEA = 0.07 [0.07, 0.08], CFI = 0.98, TLI = 0.96, SRMR = 0.02) and was carried over into the final SEM model. The reliability coefficient of the eight items was α = 0.94.

3.2. SEM Results

The main results are reported in Figure 4. The model controlled for the child's age, sex, native language, and a cumulative socioeconomic risk index.

FIGURE 4.

Structural equation model with three mediators in parallel. **p < 0.01. **Standardized regression coefficients are reported. The covariables are not shown for visual parsimony, but the model controlled for the child's age, native language, sex, and a cumulative socioeconomic risk index. The ovals represent latent variables. The rectangles represent manifest variables. Correlated residuals were added between items of the latent variables. These post hoc modifications are described in the Result section. Source: Data compiled from the file of Résilience Parents (2023), Gouvernement du Québec, Institut de la statistique du Québec.

Children with school readiness vulnerabilities experienced greater learning difficulties during the pandemic, with a weak‐to‐moderate effect size (standardized regression coefficient β = 0.24, p < 0.001). In turn, learning difficulties during the pandemic were associated with lower academic achievement postcrisis, over and above children's vulnerability (β = −0.49, p < 0.001) with a large effect size. A partial mediation was observed where the association between school readiness vulnerabilities and academic achievement postcrisis dropped from β = −0.29 to β = −0.18 (p < 0.001) due to the presence of learning difficulties during the pandemic in the model (indirect effect: β = −0.12, p < 0.001).

We did not observe a significant association between school readiness vulnerabilities and lifestyle changes (β = −0.01). However, lifestyle changes were significantly and weakly associated with academic achievement, although in the opposite direction expected (β = −0.08, p < 0.001). More specifically, positive lifestyle changes predicted lower academic achievement postcrisis. Finally, positive lifestyle changes also predicted fewer learning difficulties during the pandemic, as expected (β = −0.32, p < 0.001).

Exploratory moderation analyses: The main results showed that children with school readiness vulnerabilities experienced more learning difficulties during the pandemic, but not significantly more lifestyle changes. This was unexpected, given that learning difficulties and lifestyle changes are moderately associated (β = −0.32). To investigate further, we conducted an exploratory moderation to test whether learning difficulties moderated the link between school readiness vulnerabilities and lifestyle changes (Figure S1). The interaction effect was nonsignificant, indicating that the impact of school readiness vulnerabilities on lifestyle changes did not vary across levels of learning difficulties. In other words, the presence or absence of learning difficulties did not modify the association between school readiness vulnerabilities and lifestyle changes.

4. Discussion

The results supported the hypothesis that school readiness vulnerabilities before the pandemic were associated with greater learning difficulties during the pandemic and lower academic achievement postcrisis. However, the hypothesis that such vulnerability would be associated with more negative lifestyle changes during the pandemic was not supported. The results supported a partial mediation whereby school readiness vulnerabilities predicted lower academic achievement through their effect on learning difficulties, but not through lifestyle changes. Notably, learning difficulties during the pandemic remained an important predictor of academic achievement postcrisis even after accounting for school readiness vulnerabilities, sociodemographic factors, and lifestyle changes.

4.1. Lifestyle Changes During the Pandemic

Similar to other studies [9, 10, 11, 12, 27], a majority of children manifested an important increase in screen time, as well as negative impacts on physical activity and school motivation, as noted by parents. In addition, about one third of parents reported negative impacts on children's relationships with friends and mental health. Positive impacts were reported for their relationship with siblings and friends for 15% and 9% of the sample, respectively.

Despite an overall negative impact on children's lifestyles, we found no significant difference between vulnerable and non‐vulnerable children in their lifestyle changes. This result seems to contradict evidence that the pandemic disproportionately affected children with disabilities [28] and those from socioeconomically disadvantaged backgrounds [29]. However, most of these studies did not directly compare children with and without vulnerabilities. Moreover, most national‐level reports point to substantial variability in children's experiences across families. For example, early pandemic data from Statistics Canada [30] indicate widespread disruptions to children's routines, social interactions, and learning environments, with considerable heterogeneity in how these disruptions were experienced. Likewise, the UK COVID‐19 Inquiry [31] highlights the diversity of children's experiences, documenting both negative impacts (e.g., disruptions to education and mental health) and, for some, positive impacts such as increased family time.

Some studies observed that a subpopulation of low‐attaining children benefited temporarily from school closures. These children enjoyed a more relaxed rhythm, reduced pressure from school, and less stress from social interactions [32, 33, 34, 35]. This could potentially account for the positive association observed in the current study between positive lifestyle changes and lower academic achievement postcrisis. More specifically, children who benefited from the pandemic may also have been those who identify less strongly with school, manifest lower academic achievement, and prefer engaging with other passions. These children might have experienced the pandemic as relatively relieving, which could be reflected in more positive lifestyle indicators, while nevertheless manifesting lower academic achievement following the crisis. Further research is needed to explore this hypothesis. This being said, considering that the association between positive lifestyle changes and lower academic achievement was small (β = −0.08), its clinical significance remains limited.

An additional consideration is the use of parental reports to assess children's lifestyle changes. Parental reports reflect subjective appraisals of change, which may be influenced by baseline expectations, stress levels, and standards for “typical” routines. Among children without vulnerabilities who may be starting from a more stable baseline, lifestyle changes might have seemed more pronounced, amplifying the perceived negative impact from parents' perspective. These children might have faced an unstructured living environment, or learning difficulties, for the first time. By contrast, children with a vulnerability who typically rely on adults' support may be more used to experiencing turmoil. Hence, both populations of children may have experienced changes in their lifestyle for different reasons. Evaluating the rates of change and including children's baseline lifestyle could help disentangle these effects.

4.2. Academic Achievement of Vulnerable and Non‐Vulnerable Children

Children with school readiness vulnerabilities were more likely to manifest learning difficulties during the pandemic (β = 0.24). In turn, learning difficulties during the pandemic were associated with lower academic achievement 2 years postcrisis (β = −0.49). While the effect sizes are notable, this pattern aligns with existing research on learning difficulties and academic achievement [36, 37]. Importantly, these findings highlight that learning difficulties during crisis periods act as a distinct risk factor, even after accounting for early vulnerabilities and sociodemographic factors, signaling that these difficulties are not fully explained by what children brought with them into 2020—they are an added burden.

Our findings highlight the importance of early identification and ongoing monitoring of children at risk for learning difficulties, particularly during periods of educational disruption. Screening for school readiness vulnerabilities before and during school entry may help identify children who are more likely to experience academic challenges under disrupted learning conditions. But our results suggest that not all children with early vulnerabilities are affected in the same way, underscoring the need for continuous monitoring rather than one‐time classification.

4.3. Implications for School Health Policy, Practice, and Equity

In practice, school‐ and community‐based programs should prioritize targeted and adaptive support for children experiencing learning difficulties as they emerge, rather than relying solely on preexisting risk profiles. Interventions could include tailored academic support, guidance for parents to reinforce learning at home, and efforts to maintain routines that support well‐being and engagement. Embedding regular assessment and feedback mechanisms within school systems may also allow educators to respond more dynamically to students' evolving needs during periods of disruption.

Research underscores the importance of maintaining students' engagement and connection to school when typical learning structures are disrupted. More broadly, children's resilience in educational contexts involves a shared responsibility to sustain learning, motivation, and a sense of belonging to school despite ongoing disruption, uncertainty, or stress. Strengthening teacher–student relationships and fostering positive peer interactions can help buffer the negative effects of disruption and support continued engagement in learning [38]. School‐based social–emotional learning programs have been shown to promote both academic and psychosocial outcomes [39, 40] and may represent a key lever for supporting vulnerable students during and after crises.

Going forward, children may benefit from a school curriculum that more effectively integrates their interests into the learning process. A “learner‐inclusive” approach [36], for instance, engages students in decisions about what is learned, how it is explored, and how learning is evaluated. By allowing multiple ways to meet instructional goals, these approaches foster greater flexibility, engagement, and motivation among students who are less strongly oriented toward traditional academic formats.

In addition to supporting students, particular attention should be directed to the well‐being of educators. The pandemic placed substantial demands on teachers, who were required to rapidly adapt instructional practices while managing evolving public health constraints and personal stressors. Although some evidence suggests growth in aspects of teaching efficacy, increases in exhaustion and disengagement have also been reported [41, 42]. Across Canada, teachers repeatedly report feeling undervalued by their communities and the government [43]. Supporting teachers' well‐being and professional capacity is essential to enabling them to effectively support students, particularly those experiencing learning difficulties [38, 44].

Together, these strategies may help mitigate long‐term academic disparities and promote more equitable outcomes, ensuring that children most affected by crises are identified early and receive timely and effective support.

5. Limitations

The findings of this study should be interpreted alongside its limitations. First, we relied on a single item to measure learning difficulties. This prevents us from estimating internal reliability and may not fully capture the complexity of the concept being measured. This limitation was to some extent counterbalanced by the use of latent constructs to assess the other variables of the model. Latent constructs reduce measurement errors and therefore strengthen the reliability of the conclusions. A strength of this study is the use of the Early Development Instrument to assess school readiness. The latter is a validated standardized instrument enabling national and international comparisons.

Second, children's learning difficulties and lifestyle changes were subjectively assessed by parents. Judgment standards may vary from one parent to another. Therefore, our conclusions speak to the importance of parental perceptions in judging the difficulties of their children. We did find strong associations between parental perceptions of learning difficulties and teachers' evaluation of academic achievement 1 year later, which supports the convergent validity of these measures.

An important strength of the current study is its large representative sample and longitudinal design with data points spanning 5–12 years of age. We used a weighting procedure to maintain the representativity of the sample to the Quebec population. In addition, this study used pre‐crisis, during‐crisis, and post‐crisis data, which allows us to disentangle the effect associated with the pandemic. However, this study did not measure children's lifestyle and learning difficulties before the pandemic, preventing a thorough pre–post comparison. Another strength is the reliance on multiple informants (parents and teachers), which limits the problem of common method variance. However, the current study did not test the role of other potentially important explanatory factors such as reduced school pressure, baseline lifestyle, and conduct problems, which should be investigated by future studies to gain a better understanding of the experience of children during the pandemic.

6. Conclusions

Parents in Quebec reported that the pandemic had the most negative impact on children's screen time, physical activity, school motivation, peer relationships, and mental health. Contrary to expectations, children with early vulnerabilities in school readiness did not show significantly more negative lifestyle changes compared to their peers. However, they were more likely to experience learning difficulties during the pandemic and to demonstrate lower academic achievement 2 years later, as reported by teachers.

These findings suggest that the effects of early vulnerability in school readiness may be more strongly reflected in academic and learning‐related processes than in lifestyle behaviors. They underscore the importance of early identification and sustained support, as learning difficulties emerging in such contexts may have lasting implications for academic trajectories.

Funding

This work was supported by the Observatory for Children's Education and Health (RQC00384), the Fonds de Recherche du Québec, the Quebec Ministry of Health and Social Services, the Quebec Ministry of Education, and the Quebec Ministry of Higher Education.

Ethics Statement

Ethical approval for all phases of the study was obtained from the appropriate institutional review committee, namely the ISQ ethics committee or the Sainte‐Justine Research Center committee. At every phase of the study, parents, teachers, or children provided informed consent as appropriate.

Conflicts of Interest

The authors declare no conflicts of interest.

Supporting information

Data S1: Supporting Information.

Table S1: Changes in lifestyle during pandemic (2020–2021) among children with and without a vulnerability in kindergarten (2017).

Table S2: Fit indices for the latent construct measurement models.

Figure S1: Serial moderation model with learning difficulties as moderator.

Data Availability Statement

The data that support the findings of this study are available from Institut de la Statistique du Québec. Restrictions apply to the availability of these data, which were used under license for this study. Data are available from the author(s) with the permission of Institut de la Statistique du Québec.