TicTacToe-Ception
I call this game TicTacToe-Ception. It is a 9x9 version of tic-tac-toe organized in such a way that 9 regular tic-tac-toe boards are set inside one larger board. The goal of the game is to win three smaller boards in a row. The catch is that after a player makes a move, the next player must play in the smaller board corresponding to the position of the last players move. The game will automatically indicate which board should be played in next, so don't worry if this seems confusing. Anyone can pick up this game rather quickly!
Bat Shooter
Here's a game I wrote from following this tutorial. You will have 60 seconds to shoot as many bats as you can. To shoot the bat, simply click on it. The bat will move faster after each time you click and you lose points for each missed shot. "But why are we shooting poor innocent bats?!?" Well try to imagine that these aren't just your typical, harmless bat. In fact, you are actually shooting vampires.. well, a single vampire. Who keeps on regenerating and is pretty much immortal. Turns out you're wasting you're time here.
Haxatron2000
Here's a game I wrote from following this tutorial. In this game you play the role of a computer virus. You must use the arrow keys and follow the available pathways towards the exit. On your way you must avoid various firewalls and antiviruses that will kill you. The good thing is that since you're just a computer program a copy of yourself will just be uploaded over and over whenever you get deleted so you can't really lose the game until you give up. Unfortunately, you might end up giving up. This game is kind of difficult.