DC Youth Orchestra (at Eastern Senior High School, 1700 East Capitol Street NE)

A full day of rehearsals, masterclasses, and sectionals for advanced students on Saturday at 8:30 AM. You can sign up right here. Musicians will perform a free concert for the public at 7:00 PM the same day.

New to music? From 9:00 to noon, visit the Open House & Petting Zoo — meet the instruments and try them out.

The Posse Foundation (at Southeast Tennis and Learning Center, 701 Mississippi Avenue SE)

The Posse Foundation identifies, recruits, and trains incredible young leaders from urban public high schools and sends them in “posses” to top colleges. Volunteer to help out with Posse’s first stage of Dynamic Assessment Process (DAP) and identify young people who have outstanding leadership qualities on Saturday at 8:30 AM. Call Andres Maldonado at (202 ) 347-7071 x221 for more info.

Potomac Conservancy (at River Center at Lock 8, 7906 Riverside Drive, Cabin John, MD)

Help the Conservancy clean up and beautify the land and water surrounding Lock 8, and along miles 8 and 9 of the C&O Canal towpath on Saturday from 9:00-11:00 AM. This monthly cleanup day is open to all ages. Just make sure to wear clothes that can get dirty.

Literacy Council of Northern Virginia (at James Lee Community Center, 2855 Annandale Road, Falls Church, VA)

Interested in volunteering with the LCNV? This Saturday at 9:00 AM, train to to administer the Best Plus Oral Proficiency for classroom program students. All the sign-up instructions are right here.

Capitol Hill Arts Workshop (545 7th Street SE)

Join forces with neighbors, friends, and new folks on Saturday from 9:30 AM-12:30 PM to create a garden out of recycled materials and learn about Rett Syndrome in the process. The garden will be featured at the Girl Power 2 Cure gala later in the month; artwork from the garden will be sent to children affected by this syndrome.

Hospice Caring (at Bohrer Park, Gaithersburg, 518 S. Frederick Avenue, Gaithersburg, MD)

On Saturday from 1:00-3:30 PM, the Wings of Caring Butterfly Release will begin with a remembrance of September 11, 2001, and follow with a dedication of memorial bricks and pavers in Hospice Caring’s Cottage garden and the reading of the names of those remembered and honored. Butterflies may be sponsored with a $35 donation.