My 3.5yo likes any kind of coloring toy (recent hit: little toy cats and dogs you can color with markers, wash, and color again but honestly any new coloring book and crayons/markers would do), magnatiles, books, blocks, playground balls (crocodile creek is a good brand), her little brother’s busy board, her balance bike, and making forts/slides/trains with our chairs and blanket and pillows (I think they make toddler-specific furniture for this if the family has space and the parents don’t want their own stuff to be constantly repurposed and destroyed).