My 13 year old just finished and flew his Rascal electric RC plane. It is available in either ARF or complete kit, and is a good basic trainer (no ailerons though).
If you want to go with gas my other boys both started on Kadet LT-40's. Again, ARF or full kit is available. Larger plane, full controls, and easy to learn on.
Keep in mind that airplane kits are almost universally without engine, radio, covering. The ones I mentioned are pretty well else complete except you also need batteries for the electric.
The others are right that there are better forums for this, however if you ask 10 modellers you'll get 10 different answers as well. If you have a local hobby shop or flying club check them out and ask their advice.
Enjoy the hobby!
Bruce
PS:
If you're new to this make sure you get a radioo that is compatible with someone else's so you can 'buddy up' as a student/instructor. This will hopefully keep your new creation from becoming a smoking hole on the first flight.