1. Large blocks. So obvious that they often get overlooked, blocks help your child learn to use both hands to complete a task and strengthen his fingers as he tries to stack the blocks, says White. Most 13-month-olds can put one block on top of another.

2. Shape sorter. Pediatricians always wear stethoscopes; occupational therapists are never without shape sorters. These toys teach toddlers to match a shape with its corresponding hole and demonstrate cause and effect when the shape is dropped into the bucket.

3. Large-piece puzzles. Start on puzzles with simple shapes (circle or square, for example) that easily fit in whether right side up or upside down. Then move on to ones with cutout pieces that can only fit in one way (like a cat or dog). Puzzles foster knowledge about shape matching as well as in and out.

4. Push toy. "Toddlers can move faster with push toys because of the support, which is fun for them," says White. "And since many of these toys play music or have other features, your child learns to concentrate on walking even when distracted by exciting things." Who knew a bubble-blowing lawn mower offered so much?