Level 304 is impossible to achieve, mathematically speaking. It takes about 195 and a half days just to reach level 200. Even if we factor in double experience, there is NO MATHEMATICAL way anyone could achieve level 304. You people need to learn to hack better >.<
Marcaliss: Your score is determined by three factors. Number one is just killing enemies. I believe you get more points for killing them before they loop, but I'm not sure. If you want more points, use angel dolls. They double the score granted from kills, but only by /that/ mushroom.
Secondly, sending new waves gives points. 10 per second sounds right, although I never actually counted.
Third, lives left at the end of the level give points. Each life is worth 1000 points, and if you have 125 lives (the absolute maximum, with three upgrades), you'll get 125000 extra points.
 "A Knight's Story"){kind=icon}
 "Mushroom Revolution"){kind=icon}
 "Hedgehog Launch"){kind=icon}