The RSVP Bone Builders class increases muscular strength, balance, and improves bone density. Classes offer a series of weight training and balance exercises. Participants must have a doctor's permission to attend. This program is held on Tuesdays and Thursdays from 9:00am- 10:00am for a $1.00 donation. This class is held at Veterans Hall, 31 West Broadway, Derry. Please call Derry Parks & Recreation for more information 603-432-6136.