☆.A.
My son is 8. It has been our tradition since he was about 3 to set up the platform, tree in the holder and trains on the day after Thanksgiving. Last year (at 7) I would say was the first year he was able to operate them by himself completely (put them on/off tracks, remember to turn on/off the power box reliably, etc.) But he has LOVED it from day #1!