Please find attached a nice PDF I have on Alberta Spruce Bonsai Care. It talks about everything needed for a beginner regarding watering, feeding, prunning, repotting, temperature etc.
I have also read from one of the forums here that picking the needles off of the branches might prevent them from thickening properly and can lead to reverse camber. Meaning that the branches at the top can get thicker than the ones at the bottom which would lead to a worse overall visual effect.
Also note that the area of most growth is at the top, the middle being average growth and the bottom being the slowest growth. So you might not want to heavy prune the bottom since it takes a longer time to recover.
This is also some good advice I got from
Soldano666 which has a very nice Alberta Spruce composition:
"Growth almost always wants to grow straight up, so keep that in mind when wiring and styling, mist of my heavy pruning is done while dormant in the winter, so it bleeds less sap."
Further reading on bonsai4me regarding the dwarf alberta spruce can be found on this link:
http://bonsai4me.com/AdvTech/ATPiceaPruningstylingandwiring.htm
Hope this helps. It's great that he wants to start at 15. It will definitely require effort to master the patience for it at this age, but if he keeps up with it then he can create a lot of great bonsai. Probably the best thing would be to look back on the spruce 10 years from now and say "this was my first one."