This "clicker game" started as part of the code.org curriculum but was enhanced:

• background scrolls
• turret placed in bottom right of screen
• asteroid decreases in size as score increases
• laser beam is displayed
• sound effects

Based on the assignment at code.org in the AP CSP curriculum, this project was enhanced:

• Player 1 / 2 chosen randomly to start
• Colors get progressively closer to one another as the score increases
• Colors may be either lighter or darker
• There are multiple ways to win/lose
• There is an options screen
• Solitaire mode was added

This runner game has lots of features... health, high score leader board, enemies, running (WAD), shooting (click), and it gets progressively more difficult after certain distances are reached. All music was created by the author, and the graphics are all original too, in conjunction with another student.  

Are you looking for an easy stress-free shooter game? If so, skip this one! The walls limit where you can manouver, and ghosts go right through walls (duh). The ghosts also get larger as time progresses.

This platform game has foliage! Some you can walk on, some you walk through, but all of it green and beautiful. Also to be appreciated are the sloped pathways and don't miss the hidden room full of gems and coins to collect!

This variation of the platform game is fun... look at all of those snails! Can you feel them crunching under your feet? And look out for falling snails, I understand they can be a real problem this time of year!

This platform jumper adds gems to collect! The layout is very enjoyable. What's your high score?

The addition of a new type of enemy adds some excitement! The layout is quite large and enjoyable, with coins to collect, sloped ground, and walk-through tiles.

This platform game has been enhanced by the addition of stars to collect. The layout is quite good. Can you collect 10 stars before the snails destroy you?

In this variation, the monsters get 20% faster every 10 seconds.  Before long you will need the machine gun (click right mouse button). I think it would be fun to create an amalgamation of all of the various shooter games (WASD, different types of monsters, gems, health, etc.).