Spock

Spock is an XO activity and pygtk application that implements a simple text editor with an embedded proof verifier. The proof verifier is based on the Ghilbert proof language, with some modest extensions. Ghilbert in turn is inspired by the Metamath project. Spock, Ghilbert, and Metamath can express a wide variety of logics and theories.

The activity could be used as the basis for a course on elementary propositional or predicate logic (or even set theory), however as yet very little work has been done to make the activity friendly to children, and introductory materials are not yet available.