Author	Location	Child Age	Play Materials
Hamadani et al. (2010)	Bangladesh	Under 2	Toys for playing music, drawing, writing, constructing, stacking, building, moving (e.g., balls, bats), learning shapes and colours, and pretending (e.g., dolls, tea sets). These objects were homemade and found in homes, outside, and toy stores.
Jaggy et al. (2023)	Switzerland	2 to 5 years old	The material condition—a standardized set of firefighter-themed role-play materials, including structured items like helmets and unstructured items like wooden blocks and silk scarfs. New materials were introduced in each session, such as crowns and medical kits, except for the last. The play tutoring condition—same materials, but adults tutored social pretend play. The control group engaged in free play and handicraft activities.
Jaruchainiwat et al. (2024)	Thailand	3 to 5 years old	A photograph of the indoor loose parts kit showed a variety of materials, including pompoms, small pipes, small wooden cubes, yarn balls, stones, etc. The authors did not provide descriptions of the full range of materials.
Lehman (2014)	United States	3 to 5 years old	Blocks, LEGOs, sand, water, commercial, educational toys (e.g., Lite-Brite©, puzzles, sorting cups, bead stringing), toy vehicles and work machines (e.g., cars, trains, trucks, backhoe loaders), dress-up items, playhouse, toy kitchen, dishes, and plastic food.
Liddell and Masilela (1992)	South Africa	2 to 6 years old	The study investigated 16 different play materials grouped into six functional categories: School-readiness materials included a number sorter, a shape and colour sorter, and large wooden number dice. Drawing/Posters consisted of large A3 scribbler pads with wax crayons and two child-height conversation posters depicting familiar scenes for black South African children, such as daycare and farm life. Puzzles comprised seven wooden puzzles, sampled twice each, showing familiar scenes like vegetables, a child’s face, and a cow in a field. Construction Blocks included four types of commercially available blocks—Duplo (3), Alex School System (3), Kwikslot (plastic rods that are inserted into one another) (4), and Buksy wooden floor blocks (4). Fantasy Toys featured two dolls (5), four toy cars (5), and a set of small-town replicas with houses, trees, schools, churches, trucks, and people (4). Miscellany included two wheelbarrows (7) and two large multi-coloured balls (7).
Lloyd and Howe (2003)	Canada	4 to 5 years old	Various play materials: open- and closed-ended
Luo (2023)	China	3 to 6 years old	Outdoor physical materials for outdoor environment activities. Various indoor game activity areas and activity materials. The general social-psychological environment between teachers and children communicating and interacting. Curriculum implementation of plan execution, life activities, learning centre activities, and teaching activities. They used colourful pictures and small pictures for language development.
Lysyuk (1998)	Belarus	2 to 4 years old	Small dolls, six wooden blocks of different shapes, clay, a box with coloured pencils, and paper.
Maker et al. (2023)	United States and United Arab Emirates	4 to 6 years old	Variety of materials including instruments (keyboard, ukulele), balls, cones, materials of hats, masks, glasses, various clothing, figures of people and animals, miniature furniture, and blocks of various shapes and colours.
Malone et al. (1994)		2- to 6-year-olds	Three sets of toys for children’s independent play: a mixed set with various play materials (blocks, dolls, animals, trucks, tools, cloth, puzzle), a set focused on doll play (dolls, action figures, nesting cups, mirror, brush, comb, cloth, basket), and a set centred on vehicle play (plane, puzzle people, wagon, blocks, bulldozer, basket). Classroom play: a wide variety of toys (e.g., doll play materials, housekeeping materials, assorted toy vehicles, blocks, puzzles, books, manipulative toys).
Masek et al. (2024)	United States	2 to 3 years old	Four material sets were used: A picture book; a shape sorter, including 12 shapes; a magnet board, including 25 magnetic shapes; and a grocery shopping set, including a cash register, play money and play food items.
McCabe et al. (1996)	United States	5 years old	Study a: For each play activity category, three familiar activities were selected. Functional activities included Styrofoam packing pellets, goop (cornstarch and water), and play dough with tools. Constructive activities involved Lego Duplo blocks, magic markers with paper, and collage-making materials. Dramatic activities featured dress-up clothes with a toy cash register, Fisher-Price playhouses with figures and cars, and toy trains with tracks. Study b: Functional activities included a water table with cups, scoops, goop, and play dough. Dramatic activities featured dress-up clothes with a toy cash register, Fisher-Price playhouses with figures and cars, and toy cars and trucks with a town-themed play mat.
McCabe et al. (1999)	United States	5 years old	Functional play included Styrofoam packing pellets in a cardboard box, “goop” made from cornstarch and water, and Play-Doh with tools. The constructive play involved LEGO DUPLO building blocks, markers, stencils, paper, and collage-making materials with glue. Dramatic play featured dress-up clothes with a toy cash register, Fisher-Price playhouses with people and cars, and Brio trains with train tracks.
Morgante (2013)	United States	3 to 4 years old	Children played at a sensory table filled with either rocks, sand, soil, or water (equal amounts). They were provided with one of two sets of materials stored in clear plastic boxes. Objects in each box were perceptually similar and matched for function (e.g., digging, pouring, containment); they varied in their realism. The minimally structured set included items that loosely represented realistic objects and had multiple uses. Examples from this set included animal and sea animal cookie cutters, plastic tubes, small buckets, wooden dowels, plastic soap dishes, spoons of assorted sizes, doll clothespin-painted people, and wooden block-shaped vehicles. The highly structured set featured more realistic objects, each with a specific function. Examples from this set included animal and sea animal figures, plastic flowerpots, silk flowers, small boats, insect figures, cake pans, Disney’s Little Einstein figurines, garden shovels, and fruit-shaped sponges.
Morrissey (2014)	Australia	Under 2	Various play materials: Level 1: Simple items like a teddy bear, plastic cups and utensils, a small basket, a baby hairbrush, and a tablecloth. Level 2: Expanded to additionally include wooden blocks, material squares, a metal teapot, a doll’s pillow, a plastic truck, and small animal figures (e.g., cat, dog, cow). Level 3: Included similar items as Level 2, but added a doll, assorted wooden blocks, a plastic plate, and a bath duck, offering a more complex and varied set of materials for play.
O’Connor and Stagnitti (2011)	Australia	5 to 8 years old	Four play stations with materials for doll play, transportation, construction, and a home corner
Pepler and Ross (1981)	Canada	3 to 4 years old	Study a: Five distinct sets: animals, vehicles, regular shapes, random shapes, and squares. Additionally, one set consisted of nine different-coloured pieces that fit into a white form board. Study b: Five distinct sets: animals, vehicles, regular shapes, random shapes, and squares. Additionally, one set consisted of nine different-coloured pieces that fit into a white form board.
Rogers (1984)	United States	3 to 6 years old	Play materials and their accessories were contained in 23 different centres: block centre, easel centre, play dough centre, art centre, dress-up centre, water/sand/salt centre, loft centre, building centre, chalkboard centre, puzzle centre, book centre, music centre, toy centre, games centre, workbench centre, puppet centre, science/nature centre, math centre, push-pull centre, perceptual-motor centre, self-propulsion centre, doll centre, and home centre.
Saracho (1992)	United States	3 to 5 years old	Various play materials: small unit blocks, large hollow blocks, block accessories, tricycles, and small pieces of equipment such as puzzles, rods, or peg sets.
Thepsuthammarat et al. (2012)	Thailand	Under 2	Various play materials: push/pull toys, home utensils, sound-making toys, junk materials, dolls and other soft toys, natural materials, storybooks, creative materials, writing materials, self-invented toys, stacking toys, and musical cassettes.
Tizard et al. (1976)	The United Kingdom	3 to 4 years old	Fixed exercise equipment, wheeled vehicles, ladders, large blocks, small construction toys, formboards, paints, clay, sand, dolls, and miniature cars with garages and trains.
Tomopoulos et al. (2006)	United States and United Arab Emirates	Under 2	Rattle, toys on a ring, soft squeeze toy, mirror, soft person or clown, sock rattle, black-and-white pattern items, activity and manipulative toys like pop-up toys, toy instruments, stacking toys, snap beads or links, blocks, push-and-spin toys, and shape sorters. For imaginative play, options include stuffed animals, bath rubber ducks, word-recognition toys, toy telephones, dolls, small cars or trucks, toy radios, and bath boats.
Trawick-Smith (1990)	United States	3 to 6 years old	Toy telephone, wheel of a car, cardboard box, doll, cups.
Vieillevoye and Nader-Grosbois (2008)	United States	2 to 5 years old for typically developing group; 6 to 13 years old developmentally challenged group	Four scenarios with four types of materials: tea party, doctor, transportation, and symbolic creativity.
Wolfgang and Stakenas (1985)	United States	3 to 6 years old	Fluid construction materials (e.g., paints or clay) are malleable, allowing children to create representational products. Structured construction materials (blocks or puzzles) maintain their shape, enabling the creation of representational products. Micro-symbolic materials are small, hand-held toys representing real objects (miniature soldiers, dolls or cars). In contrast, macro-symbolic materials consist of child-sized equipment and props used in socio-dramatic play. Physical materials include objects or equipment (e.g., balls or climbing frames) primarily designed for sensorimotor or physical activities.