It can’t be possible… no…. noooooooes! K-On! is coming to an end and so does my life ;_;
Anyway…. about this episode….
The school festival is right around the corner and Yui’s guitar is, simply put, fucked up. The strings have rust, the neck is bend and it’s plainly dirty…
Good ol’ Yui doesn’t understand anything about it and insists she takes care of her guitar:

Sawako is too lazy to help them fix it and so they head to the music store.
Mio is embarassed and doesn’t want to get in a store with right-handed instruments when she’s lefty. This is all gone t hough when Ritsu tells her there are left handed instruments in there.

Yui and Azusa head for the cashier who never have thought he’d see a guitar like Yui’s in such a horrible condition. With this and that, he starts fixing it and tells the girls to wander around the shop untill he’s done.
Somewhere else in the shop Oojosama-Mugi-chan is surrounded by workers who want to greet her. Finally, the guy with Yui’s guitar (Guitah, as she calls it) arrives and tells her the repair fees cost 5000 yen.
Yui, who didn’t actually think they’d ask money for it, is in a
shock as she hasn’t got any money with her. But anyway Mugi saves the day again as she owns the shop.

I feel sad about the guys there though, that’s the second time they dont get any $$ from Yui. (Well, she payed for the guitar but… only the 1/5 of its original price)
The rest of the episode is centered around Mio’s relationship with Nodoka and how Ritsu is jealous. In the end she ends up with a fever but gets better later on.

Oh, I almost forgot to mention the spy girls:

Also, the band has now a name: “Afterschool teatime”