Here are my top 10:

1. Part of Me
2. Firework
3. Teenage Dream
4. The One That Got Away
5. California Gurls ft. Snoop Dogg
6. E.T. (no featuring)
7. Last Friday Night (T.G.I .F)
8. Hot N' Cold
9. Who Am I Living For?
10. I Kissed a Girl