I've put together a list of planes that make good trainers and second planes. All of them on the list are proven planes that are well suited for successfully letting students learn to fly, or advance to a second plane. Check out the list here
[link=http://www.rcuniverse.com/forum/m_4537845/tm.htm] Looking for a trainer- what's available. (Updated 12-20-07) [/link]

All of the kits on this list were selected not only because they are good trainers, but also because they are good kits for the first time builder. Take a look at the list and I'm sure you'll find something that suits you. If you asked me for one in particular, I would pick the Sig LT-40. It's a great building plane and and outstanding flying plane. Plus I have a build thread on this plane that you can reference as you build the kit. You can find that build thread here:
[link=http://www.rcuniverse.com/forum/m_3439708/tm.htm]Pay It Forward build thread!! LT-40 build.[/link]

Hope this helps

Ken