Boys' Gymnastics/Open Gyms in Overland Park Area

Blue Valley Recreation center offers both classes and an open gym. They are very reasonable for both residents and nonresidents. They are located on 151st ST, their website is www.bluevalleyrec.org. Also, if they like to swim the Matt Ross community center in OP off Metcalf and Marty (near 81st St) has a wonderful indoor pool with a two story slide. I think they also offer classes but would probably be a further drive. Good Luck and congratulations on your boys!

I know there is a gym that just opened in south leawood in that new Cenntinneal Park on 143rd & State Line. It actually sits on the MO side though. Also there is Eagles gym in Martin City, MO (135th & State Line).
If you want something mid OP then there is Bellers Studio at 79th & Foster.
Lenexa there is one, which the name escapes me at this time, but it's off like Lackman & I435 or maybe it's pflumn.

Hope you find something.

B. - Congratulations on your new sons! Here is a list of gymnastics gyms that offer classes in the Kansas City metro - http://www.kckidsfun.com/classeslessons/dancegymnastics/

I've heard good things about Diamond (159th-ish and Metcalf) and Eagles (135th St just over the state line in Martin City). Another great resource for the south OP/Leawood area is Blue Valley Recreation - they have classes and open gyms. They are getting ready to do enrollment for the session that starts in January. http://www.bluevalleyrec.org/ (Their activity center is on 151st St. just east of Metcalf)

Good Luck!

My daughters were in gymnastics a few years back and the only really active boys gymnastics that I saw in the area was McCracken's gym I think it's in Olathe. At the time I knew a parent who took her girl to Great American Gymnastic Express and her son to McCracken's.
Another thought would be Soccer, it keeps a child running and I have found that being able to run non-stop helps them in all sports.