Now that they are moving on their own battery free life is easier not harder.
Look for items that will roll, rattle and make plenty of noise for this age group. Imagination is starting to take shape. Early Toys will have new meanging so your investment in toys from previous development stages can be put back into the mix.
Engagement begins to cost more than the battery powered counterparts but still fun & green
Stacking, building, racing and movement are the winners for young toddlers. Don't be afraid of puzzles and items with moving parts. Don't be affraid of items that the child can't use correctly, if it's not a safety issue let them explore concepts. Ease of Reach?
Engagement is reducing in price per minute no doubt. Getting by without batteries is fun, messy and full of learning.
After 2 years of building a child's expection of what play looks like the learning that takes place as they reach preschool is opeing up huge options. You will find that a cardboard box, bed sheet or old pan will go far in the world of make believe.