I'm totally copying Danger but, I thought I would make a longer list. (not completely my opinion)
20. Kiss 'N' Tell
19. Grow A Pear
18. Crazy Beautiful Life
17. Disgusting
16. Die Young
15. Dancing With Tears In My Eyes
14. Party At A Rich Dude's House
13. Harold Song
12. Sleazy
11. Boom Boom Bang
10. Animal
9. Dinosaur
8. Cannibal
7. Backstabber
6. Your Love Is My Drug
5. Take It Off
4. We R Who We R
3. Warrior
2. Run Devil Run
1. Crazy Kids
Honorable Mentions: Tik Tok, Blah Blah Blah, My First Kiss #Kesha