For 3-year-olds
At three, collecting is mostly gathering and touching: picking up what catches the eye, lining things up, putting them in a container and taking them out again. Children this age start noticing that objects belong to groups, big and small, this colour and that one, which is the beginning of sorting. Look for a series with a slow pace, plenty of time on each object and simple, repeated words for what is being collected. Stories that end with everything safely in its place suit this stage better than ones about winning or losing pieces.