At a fair this past summer, I was helping some kids make paper airplanes. A guy at the fair gave me a foam glider. I told him I was going to make the glider RC.I used 4 servos for this glider.(they weigh about 9g each). I put 2 servos on the wing.
I cut out and used plastic from an empty laundry detergent bucket, to make the firewall and the control horns (you could probably use other kinds of plastic or wood for the firewall and control horns).
Here's the video of me making the glider Remote Controlled and FLYING IT! (I was flying this glider with a 2s battery)