The Going Out Guide recommends free things to do for every day of the week:
A saxophone-only quartet may sound like an abrasive experience, but Mana pulls off its collaboration with grace and subtlety. As part of Washington College’s National Music Festival, the four musicians will be performing brass chamber music for free on Monday.
5 p.m., Betterton Community Center, 100 Main St., Betterton. 410-778-2064. www.nationalmusic.us.
Musicians from the local mainstay Friday Morning Music Club perform works by John Antes and William Shield. The classical period pieces performed on stings and fortepiano, as well as choral works, commemorate the War of 1812.
7:30 p.m., Dumbarton House, 2715 Q St. NW. 202-337-2288. www.dumbartonhouse.org.
If you’ve ever perused the comment section on a Youtube video, you may have noticed how quickly hateful material can grab attention and snowball. Abraham Foxman, head of the Anti-Defamation League, and Christopher Wolf, privacy and data-security law expert, have studied the online propagation of angry rants and how violent words sometimes turn into violent actions. The two will discuss the findings in their book “Viral Hate: Containing its Spread on the Internet.”
7 p.m., Politics & Prose Bookstore, 5015 Connecticut Ave. NW. 202-364-1919. www.politics-prose.com.
Celebrating the renowned 19th-century opera star, this concert features soprano Magdalena Risberg as Jenny Lind, the “Swedish Nightingale.” She’ll be accompanied by the winner of the Royal Swedish Academy of Music’s Accompaniment Scholarship, David Huang. A reception with Swedish food follows.
6:15 p.m., House of Sweden, 2900 K St. NW. 202-546-7266. www.houseofsweden.com.
On an outdoor stage, musicians perform Latin, Irish, and Americana music as part of Columbia’s annual Festival of the Arts. Catch La Unica, Donegal Xpress, and the Ted Garber Band in front of Lake Kittamaqundi on Friday, and come back for more free music through the rest of the weekend.
Friday 5 p.m. to 9:45 p.m., Saturday noon to 10 p.m., Sunday noon to 7 p.m. 10275 Little Patuxent Pkwy., Columbia. 410-715-3044.www.columbiafestival.com.
A light satire of European-African relations and a pointed jab at colonialism, Jean Rouch’s 1970 ethno-fiction “Petit à petit” (“Little by Little”) follows his Nigerian collaborators Damouré Zika and Lam Ibrahim Dia on a trip to Paris. Rouch had spent more than 20 years documenting West Africa at this point in his career, and “Petit” takes careful aim at French conventions utilizing the cross-cultural perspective he cultivated. The film is in French with English subtitles.
4:30 p.m., National Gallery of Art, East Building, 700 Constitution Ave. NW. 202-737-4215. www.nga.gov.
North of the horse stables, inside the Rock Creek Nature Center, poets Adam Chiles and Moira Egan will recite verses from their work on Sunday. For this latest incarnation of a poetic reading tradition that stretches back to the 1976, the poets are chosen from a large pool of applicants, both novice and well-established. A reception in the lobby follows the reading.
3 p.m., Rock Creek Park Nature Center and Planetarium, 5200 Glover Rd. NW. 703-820-8113. www.wordworksdc.com.