Verish is a language for reasoning that resembles a natural language. It is equivalent to Lower Predicate Calculus, and has a built-in framework for defining and using abbreviations, and for introducing additional principles of reasoning that can be automatically expanded into a sequence of steps that use only basic principles of reasoning. It has a basic reasoning checking function, and can automatically expand one additional principle of reasoning into a sequence of steps using only the basic principles. It can also add HTML markup to a proof for display as a Web page.
Smart Challenge is a computer game to exercise logical thought by solving millions of randomly generated tangram puzzles. It allows you to create and store new puzzles and display the ranking of solution times for each puzzle. Additionally, it has levels of difficulty for the random generated tangram puzzles.