Our eldest (5) is just getting to the age where he’s showing a bit of an interest in computers (yay) also dance music (yay) and also making things. Obviously something to encourage…
I know very little about the computery side of music, but I’m guessing someone like @jonobacon will know quite a lot more 
So: what’s out there, and at what sorts of ages might it be appropriate? I’m figuring 5 is probably a bit young for anything, but it’d still be good to know and like I say I know very little about this. Also, I might need to start saving if the answer involves the words “buy a Mac” 