Divers Source at the 2/4 split heading towards Annapolis is good.
I took thier Open Water course with them through Pax River MWR in the pool on the base. Very well done and cheap. I also boutht my gear from them, but I regret not shopping around or buying from the place in Solomans because making a return was near impossible because its inconviently far away. Do the open water dives at a location (I picked Jamaica!). Diver Source takes you to a cold and dark quarry in PA. Jamaica costed ~$200 per person for the 4 open water dives, incl gear.
Anyway here's thier blurb at Pax MWR:
Scuba Classes-Try a free session of Discovery Scuba on Sept. 9 from 1-3 p.m. Students must be 10 years of age and complete a medical questionnaire for Discovery Scuba. Open Water Scuba is Sept. 8 and 9 from 8 a.m.-4 p.m. The fee is $150. Advanced Open Water Scuba is Sept. 12 from 6-8 p.m. The fee is $80. Classes are held in the Indoor Pool. Register at the ITT Office. For more information visit
www.diverssource.com or call (301) 342-3648.
You can likely get guest access to the base if you call Divers Source! Can't hurt to try.