Several theaters are located in Quito's historical centre and the northern part of the city. One of the most famous ones is Teatro Nacional Sucre, situated in a beautiful building in the old town.
The cultural centre of Quito, La Casa de la Cultura, is also frequently used for theater and other performance arts.
Opera is not a popular theater form in Ecuador, but you have the opportunity to enjoy an opera show, for example in Teatro National Sucre.
For theater plays and more information check the website of Quito Cultura.
You can enjoy orchestras at several locations in the city, both Ecuadorian and shows of international orchestras touring around South America. The national symphony is situated in Quito and performs in the city on a regular basis. For more information and programming, check the website of the municipality.
Quito has many museums, both modern and historical ones. Entrance prices is usually between $2 USD and $8 USD, and many of them do not have an entrance fee for Ecuadorians and residents on Sundays.
One of the most famous museums is El Museo de la Ciudad, located in the historical centre near the artistic street La Ronda, where visitors can learn about the history of Ecuador.
Another popular museum is El Capillo del Hombre, where the majority of the Ecuadorian painter Oswaldo Guayasamin's work is exhibited next to his house that can also be visited.
See the official website for more information on Quito's museum.