The Rockville Senior Center is challenging its members to take part in an eight-week fitness challenge that will begin Monday, March 19. Prizes will be awarded for the three senior center members who exercise the greatest number of minutes. An organizational meeting will be held at 2 p.m. Monday, March 12, for participants to receive the challenge packet and to review the program’s guidelines. Registration is required for this free program. Register by March 19 with course #4784 at www.rockvillemd.gov/registration. Must be a senior center fitness member.