He really likes to match things, and he's quite good at it actually. So our newest game is to take a pile of coloured Popsicle sticks and hand him a colour, and then he finds all the other sticks that are the same colour. (Not colour blind-check!)
The slots in the lid are just barely bigger than the Popsicle stick, so he has to line them up just right and push them to get them through. For little ones who are just beginning to work on motor control you could make the slots much bigger.