I started programming in HyperCard around age 7-8. The first things I did were basically interactive stories - think Myst with stick figures and a really childish plot/simplicity. Drawing pictures, placing buttons over them that took you to different pictures with more buttons. Dialogs with questions and multiple choice answer buttons. Eventually adding variables that would remember things that happened before and use those to change behavior later in the game.

I also had fun composing really bad melodies with the HyperCard sound command (that let you enter notes - it'd scale whatever sound effect in pitch)

edit: the greatest learning tools for me were all the included sample stacks. Tearing apart and editing those and the code that made them tick was an amazing learning experience ("oh! so instead of making 50 buttons, I can make one button, and do this thing with the mouse position and some math [something they make me do in school that I otherwise find pointless] and figure out which section was clicked!")