We bought our son a starter train set for Christmas this year. It's a figure 8 with a bridge the train can cross. I was a little worried that it might be a little much for him, since he's not even two yet, but my worries were wasted.
He loves his train set and as I have observed him play and played with him myself, I see that he is really learning from his it.
1) Gentleness
If he pushes the trains too hard or fast, they fall off the track, so I remind him to be gentle with the train. He really gets it. When I remind him, he immediatley becomes calmer and more gentle with the train.
2) Fine Motor Skills
Playing with the train set has helped his fine motor skills to develop. This goes right along with learning to be gentle. He is using basically the same skills.
3) Sharing
He and I take turns pushing and pulling the trains around the tracks. And we talk about what we are doing, your turn, my turn, etc.
4) Colors
I will ask him to push the red "choo choo" around the tracks and he'll try to do so. So far, he only knows "Yewow" but it's a benefit I had not thought about. (Not that he could not learn his colors in many other ways, but it's working for us.)
5) Fun
Most importantly, he is learning all of these things while he is having fun. He absolutely loves his train set, and that he is learning while he plays is just great.
6) Independent Play
It is also helping with our Independent Play battle, he likes to sit and play with his trains, by himself!