Table 3.

Percent of students engaged at 5 and 20 min into the observed lesson^a

Time	Teacher	n	n total	Percent classrooms engaged	z	p
5 min	Observations after BrainU 101	32	42	76	1.53	0.13
	Comparison	5	10	50
5 min	All BrainU observations	63	79	79.7	1.81	0.07
	Comparison	5	10	50
20 min	Observations after BrainU 101	30	42	71	1.24	0.22
	Comparison	5	10	50
20 min	All BrainU observations	63	79	79.7	2.46	0.014
	Comparison	4	10	40

^an represents the number of classrooms in which students were engaged out of all observations (n total). The percent classrooms engaged measure represents the proportion of classes in which students were engaged at that time point. p, z, two-tailed z-test on independent proportions vs. comparisons.