  Proof Blocks is a software tool which enables students to write proofs by
dragging and dropping prewritten proof lines into the correct order. These
proofs can be graded completely automatically, enabling students to receive
rapid feedback on how they are doing with their proofs. When constructing a
problem, the instructor specifies the dependency graph of the lines of the
proof, so that any correct arrangement of the lines can receive full credit.
This innovation can improve assessment tools by increasing the types of
questions we can ask students about proofs, and can give greater access to
proof knowledge by increasing the amount that students can learn on their own
with the help of a computer.
