All game play is done with the mouse.

Click to drop your primary bomb and then continue cicking to fire your gun (once you buy it).

Other upgrades that you buy can be activated using the number keys.

The full title is Lil' Einstein's Manhattan Project, and it takes you to his garage where you will be a test subject in his brilliantly crafted science project. The object is to upgrade your plane with new weapons and bombs in order to purchase the Atom Bomb by day 25. In order to buy the A-Bomb, you must buy all 9 other bombs which are successively stronger than the last.