You might want to spend some time browsing the exhibits at Metro Museum, New Tretyakov Gallery - Museum of Modern Art, or Museum of History of Moscow. Novodevichy Convent, Cathedral of Christ the Savior, and Pushkin House Museum on Arbat are monuments to see when you're exploring the area around Gagarinsky. You can watch performances at Great Moscow Circus, Moscow International House of Music, and Anton Chehov's Theater if you're interested in local theater.