MIT edX is holding a (free, online) class Introduction to Aerospace Engineering: Astronautics and Human Spaceflight. It starts on September 6th, 2016.
https://www.edx.org/course/introduction-aerospace-engineering-mitx-16-00x-0
I doubt they will be teaching design of Impellers and Warshawski sails, but it still might be interesting.
-- Bob G