[Joof]

Just add mods. Feed The Beast has nice modpacks and I loved watching direwolf20.

Dwarf Fortress is fun, but different. It feels more like a narrative generator to me.

Edit: unsure why this is downvoted. People don't 'graduate' to games, each one appeals to people for different reasons. If you want your kids to play a more educational game, minecraft with mods is that game.