I need some ideas of fun things to do in the Maryland- washington D.C. area?

I've already looked at kings dominion, dorney park, hershey park, the baltimore aquarium etc. One thing we're planning on doing is going to the national archives. We've already been to the smithsonian, the national museum of natural science and history, and the holocaust museum. Most of the things I listed before are pretty expensive. So does anyone know of someway i can get a discounted rate? or can somebody tell me other places that are interesting that won't be so expensive?I need some ideas of fun things to do in the Maryland- washington D.C. area?
i live in the area. go to six flags. one i know is located past mitchellville plaza in maryland, and also there's the chesapeake beach water park in St. Mary's county in maryland. try there. ummm i'll look up more for u but the things u've listed are the things we usually go to lol but i'll see if i can find u some more activites. Also go to different counties in maryland, like charles county and def. st.mary's if u want to know a little more about it's history also they have great sites there too. such as the DR. Mudd house who's great granddaughter i think, or daughter lives in the house across from his. dr. mudd is the doctor who was arrested for being accused of being involved with lincolns assination after helping booth and his accomplis with his broken leg.n it's REALLY interesting.

also go here for more ideas:http://www.thingstodo.com/states/MD/inde鈥?/a>

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