* Reserved, diligent "a-lot-has-happened-since-I-became-a-teacher" Sawa-chan's facade cracks in S2 E10 "Sensei" when people start calling Death Devil "cute" during the wedding performance. She snaps hard enough that the ''lights in the auditorium go out''.
* The first time My love is a Stapler is played on stage. Yui forgets to sing. Mio jumps in to take the words. For the shy girl she is, that's pretty awesome.
** Then they turn it into a pretty epic duet.
* The seiyuu actually playing their instruments for My Love Is A Stapler and Fuwa Fuwa Time in the Let's Go concert.
** And in the Come With Me concert, Pure Pure Heart and U&I (as well as performing Fuwa Fuwa Time again).
* The song U&I doubles as a CrowningMomentOfHeartwarming.
* The encore at the end of Episode 12 definitely counts.
* Yui improvising a whole new verse for Gohan wa Okazu during the movie.
* The concert in the classroom close to the end of TheMovie. Once again doubles as a heartwarmer due to the circumstances that lead up to, and even during it.
* The opening of the movie has the four girls playing some pretty hardcore metal out of nowhere.