by Brad Miller and David Ranum, Luther College (as remixed by Jeffrey Elkner)
by Mark Guzdial and Barbara Ericson
Hands-on introductory computer programming using Python 3.
by Jeffrey Elkner (with liberal borrowings from the work of Allen Downey,
and Peter Wentworth)
An introductory computer programming text book using Python 3.
by Peter Wentworth, Jeffrey Elkner, Allen Downey, and Chris Meyers
An introductory computer science text book using Python.
by Tony R. Kuphaldt
A free series of textbooks on the subjects of electricity and electronics