Joseph has had two train sets since his second birthday (October). He asks to play with them all the time but they only actually turn into a usable train track when one of the adults in the family has time to play, too. He was always happy to drive the trains around the carpet. I glanced over while folding laundry the other day and saw this little train track, complete with ramps at either end so the cars could get on the track more easily. All by himself!
Joseph's play has definitely reached a new level of imagination--he's also teaching his teddy bear to walk. It's a lot of fun.