All Change is a lightweight game aimed at younger kids. I was bought my copy many years ago and recently dug it out of the cupboard at my parents to play against my three year old daughter.
The aim of the game is to get two of your pieces into the same carriage of the train. Each turn, you can move any piece to an adjacent empty circle or platform or jump over any adjacent piece to an empty circle or platform. Or, if you are already on a platform, you may board the train provided the seat is empty.
Once you board the train, a dice is rolled and the train moves to the next signal with the corresponding number. If anyone on the train is next to a guard, they go back to the cente. I think the rules say you're supposed to shout 'All Change!', but I've always considered this to be an optional rule.
Once on the train, you may also move pieces along it in a manner similar to movement on the board.
There is some strategy to the game. It's no good getting all your pieces bunched up near one platform. As soon as one gets on board, the trainmoves on round the board. It's far better to try to take up a platform or two further down the line ready for when the train has moved.
This is a great game for younger kids, and my Father and I had quite a time trying to beat my daughter. Obviously, it's interest will soon dissipate amongst older players, probably from about 9 years upwards.