Scratch Final - Part 1

My game is an invader type game where you have to stop the invaders from reaching Earth! I used an earth sprite, and a spaceships for the invaders. Naturally, I have to use the stars background, because it looks like space. For every spaceship you click, you will gain one point. I may add more ships that move faster, but are worth more points. To win, you have to beat all three levels, each getting progressively harder. When someone wins, the screen will say something like "Congratulations, you win!" To increase difficulty on another level, I will add more spaceships that you have to destroy. Once you blow them all up for the level, you proceed to the next.