My favorite one when I cheered (I think it was a UCA cheer my senior year) was:
Let's get a little bit rowdy
Lions are xx Rowdy
The school I coach at now has a couple favorites:
P-U-M-P pump it up to victory
Pump it up, Pump it up, Pump it up up up up(repeat)
And of course (though the cheerleaders ONLY do this during the breakaway banner run-though with the WHOLE senior class on the field, I won'y let them start it during the game:
Ooh Ahh Ahh you wish you were a Greyhound
Ooh Ahh Ahh 'cause winners come from H-town
Ooh Ahh Ahh and losers come from dub-town (our rival is from a town called Windsor)
Ooh Ahh Ahh so now you better bow down
Ooh Ahh Ahh 'cause winners come from our town!
(repeats)
I don't even think most people know all the words, everyone just does the "ooh ahh ahh" part and the first line.
Of course they have a couple slapping/stomping cheers that everyone thinks look really cool and the crowd is always trying to figure them out
