My 4-year-old figured out on her own that only the right number and picture pair fits together, so she's basically teaching herself while I cook dinner. The wooden pieces feel sturdy enough to survive her little brother too.
Avery K.★★★★★
The self-correcting design is genius because my daughter can tell on her own when a pair doesn't fit, so she just keeps trying without needing me. We've been doing the 1-10 puzzles at the kitchen table before dinner and she's already counting the little groups of objects out loud.
Abigail X.★★★★★
My 4-year-old figured out the 1-20 matching on her own because the pieces only fit the right way. The wooden pairs have held up fine after a few weeks of daily play, and she's counting everything in the house now.