I did Paris last Spring Break. The normal big sites are good. I should have bought the museum pass but ended up paying individually. Its a worthwhile buy. If you don't want to wait in line for the Eiffel Tower I suggest going up in the Arc de Triumph. Great views, and no lines. I think I actually liked it better than the Eiffel too.
Notre Dame is on the list of course.
Montmontre and the markets on the bottom of the hill are cool. Great views from here also, worth the hike up the hill.The markets are where the royality used to sell their old flee infested clothes. Hints the name Flee Market.