My first real main project when I was 17, the codes still lives today and probably in the shape you can imagine. 2DLandz was all about fun and no restrictions, concerns of scale and maintainability (most due to incompetence). You could play locally up to 4 players, all sharing the same screen. The goal was to eliminate all players by purchasing weapons, all having a special ability.
The first project is always special, and I am happy that I have successfully saved the source code, even after so many years :)
What you can expect to learn during a Game development class in your seventeen. Game loop, what makes a game fun, state handling etc. The basics!