1.
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4.
5.
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7.
8.
9. We Will Rock You - New Direction
10. Mamma Mia - Rachel, Santana, Kurt and New Directions
11. Wannabe - New Directions Girls
12. Centerfold/Hot In Herre - New Directions Boys and the Cheerios except Artie
13. This Is The New Year - New Directions
14. Diva - New Directions Girls and Blaine
15. Getting Married Today - Will, Emma and Mercedes
16. At The Ballet - Santana, Isabelle, Rachel and Kurt
17. Outcast - New Directions
18. Superstition - Mercedes and New Directions with Mike and Kurt
19. Longest Time - New Directions:
20. You Have More Friends Than You Know - Marley, Unique, Blaine and Sam
21. Baby Got Back - Adam with The Apples

I think you forget Don't dream it's over. It's a group number but I can't find it.

@SarahCorine That's because these are all the group numbers that were after the winter hiatus. Don't Dream was before the hiatus, that's why I've named this pick "2nd half of season 4"

I Love It was amazing!!

Oh yes of course. I'm sorry, I didn't consider that. My mistake.