When you're interested in music, dance, theatre or opera, the Swedish Museum of Performing Arts - Scenkonstmuseet - is the place to go to. This rather small museum is next to Dramaten (the Royal Dramatic Theatre), which is no coincidence. This really nicely made and interesting museum has two floors. On the ground floor, you'll find the Swedish Music Hall of Fame. There are many pillars with all the information (always in swedish and english) about the artists that are part of the Hall of Fame. You'll find some known artists as ABBA (surprise!), Roxette and Europe, but also some you've never heard before when you don't live in Sweden. Even if you don't know them, it's interesting to read the stories and you can spend quite some time on it which is perfect especially when it's a rainy day in Stockholm.
On the second floor, there are changing exhibitions about performing arts. When I've been there, there was a room with big screens on all the walls where there were performances of different dancing styles from ballet to flamenco to hip-hop, and it gives you the feeling the dancers stand in front of you. In the big room you can find interesting information and stories about different arts and learn about stage costumes, shoes, stage designs, listen to artists tell about what they do and many other interesting things that make you understand performing arts better. Some pieces of their huge collection of clothes, instruments and puppets can be seen in the exhibitions. There is also a part for kids where they can try out things related to performing arts. So the museum can be visited with the entire family. There is also the bistro Kavalleriet in the same building and in summer, you can also sit outside and have something to eat or drink before or after your visit.
Find all the details about current exhibitions, opening hours and entrance fee on their website. The entry is free for everybody on Wednesdays!