In the first level, when you have to shoot all the ties, hit the event button and wait for a second. For each tie that the wingmen take out, you will get about 2000 points!
Also in the first level, in the trench, when Darth Vader and two ties swoop down, you can shoot them with torpedos! You have unlimited, so don't worry about failing.
In Hoth, when Luke says "Attack Pattern Delta, go NOW!" Repediatly press the event button. There will be a red triangle around its head. Shoot, and you will kill it! Press the event button whenever Luke says "Attack pattern Delta"
On Endor, when you are on foot, sometimes the event button will flash for a second when you are in front of a single troop. Repediatly hit the event button, and don't shoot the trooper. An Ewok will fall on his head, giving a kill, and 3000 points!
On The battle with Darth Vader, if you kill him, hit the event button, and you will hear the emporer say "So be it....Jedi"
On the final level, when the Tie Bomers are flying in, take out the last one, and IMMEDIATLY press the event button before the shuttle comes. The a-wings will hit the shuttle, and give many points for each hit!