One section asks you to learn Jack (The high-level programming language) by writing a medium-complexity program. The goal of the exercise is not to get proficient in Jack (which is a Java-like-language), but to just learn it well enough to implement the compiler.
I wrote a Tic-Tac-Toe variant - but you could write anything, including Tetris.
I wrote a Tic-Tac-Toe variant - but you could write anything, including Tetris.