Episode 8, titled School Festival, follows Festival Eve where the festival will finally take place.
This approaches the climax in the series as Koto has asked Mako to dance with her, and he is being pressured by all the girls in his life to make a choice.
Other events include a maid cafe, and a competing class who stole ideas from 2 other classes doing a combination little sister + zombie themed event.
This leads into episode 9: After Evening Festival when the dance takes place.