Another good routine is to do 10 pushups every minute for at least a half hour. Starts off really easy but when its said and done you did 300 pushups. You get to a point similar to "the wall" for runners where you can barely do ten. Then all of a sudden you're banging them out faster then you were in the beginning. Can do the same thing for sit ups.
Just a heads up, before I got out this summer there was a new format for the PT test that was supposed to be implemented in this year I believe.
A look at the Army’s new PT test - Army News | News from Afghanistan & Iraq - Army Times
Good luck and have fun on sand hill