My most challenging project to date - chess. I was able to make a visual, two player chess application. This project made very effective use of classes and inheritance - a new concept for me when developing.
Flappy Birds was my first attempt at an object oriented game and was a great way for me to learn. Despite some small issues (mentioned), I am very happy with the end result which plays similar to the real game.
Snake helped me to develop my object oriented programming knowledge. I learnt a lot about making different objects interact within a game framework class. The project also introduced me to some abstract data types such as linked lists.
Pong was my first major programming project. I learnt a lot more about procedural programming and how to effectively change the 'focus/control' in a program. I also learnt about Visual Basic's timers which has been very important in later projects.