I have done a lot of work on Autonomous control of RC cars, helis and airplanes. My applications have mostly been on stabilization and waypoints for aircraft using in inertial measurement unit (IMU) board. On the RC car, I ripped out the simple RC controls and replaced them with a Specktrum RX.TX system. I used a PIC processor to convert the throttle PWM signal into something the existing H Bridge motor controller understood and replaced the steering servo with a standard RC servo. I have a camera on a servo controlled pan and tilt servo system, and added things like the Parallax PING sonic distance sensor, and compass module and a GPS (but this only works outside). There are a lot of things you can think of adding.

Looks like you already have a real RX/TX system with a BEC/ESC to a motor. The signal going from the RX to the ESC; Red/Black/Blue(sometimes different color) are +V/GND/Signal. Signal is a Pulse Width Modulated signal whose width tells you how much throttle to apply. Typically this signal will be 3.5v (or so) and a width of 1.2 to 1.8 usec, depending on throttle setting.

Autonomous control will depend on what you want to do and what sensors you need to accomplish it. Waypoints won't work indoors with a GPS, but you can memorize a track, detect obstruction, follow a wire or tape track, lots of things.

A very sophisticated version of indoor automony is a laser scanner that basically maps its environment, but very pricey. You could try a sonar version of this using the PING sensor, lots of math and geometry involved.

Good luck and have a lot of fun with your students.

John