I see Gazebo, MORSE or Webots as options. Webots is said to be easy to use but is paid. No good low cost EDU option. MORSE is open source and python based, is relatively new. Gazebo can be run as a Virtual machine — See here.

Gazebo can also be set up on a cloud server with your students logging in via a client on their PC. Might be the best way to go given the diversity of your students and their hardware accessibility.

I am taking Front End Developer at Udacity and live in the bay area. I am really excited about the Self Driving Car Nanodegree. I am trying out some of these simulators and will let you know if I find anything that might help.