K-On!, Stella Jogakuin Koutou-ka C³-bu Recommendations
Similar characters and similar club activities.
A female main heroine forced to sign up a club in an all girl school setting then got interested after watching some of it's activity sounds perfectly similar to me.
Cute girls doing cute things but with guns. Add some cake and tea from time to time too.
Both series features an all female cast where they are part of a group/team. As such, they often hang out together doing various activities. The difference though is K-On! is more music oriented while Stella Jogakuin Koutou-ka C³-bu packs some action involving guns and competitions.
However, both series has a lighthearted atmosphere in a school life environment. Additionally, some of these activities puts together teamwork at test. Oh and let's not forget about the tea...the delicious tea and cake....