Preschool sandboxes cover toddler to early-elementary ages — listings commonly show recommended ages from about 18 months up to around 8 years, with many products targeted at 3+ years.
Common materials include wood (fir or cedar) and plastics such as HDPE/polyethylene and polypropylene. Many products pair wooden frames with plastic liners or components for durability and easier cleaning.
Sizes range from compact tabletop sets to large backyard pits. Example listings show tabletop sets around 38" x 30" x 21", mid-size pits about 50" x 46" x 16.5", and large octagon models near 85" x 85" x 9".
Many sets convert between traditional sandbox play, sand-and-water sensory tables, picnic/table seating, and storage or toy-organizer functions, depending on the design.
Options include adjustable canopies or umbrellas for sun protection, removable lids or elastic fabric covers to shield sand from debris, and novelty lids (for example a volcano-shaped cover) that double as storage.