I hunted around the Girl Scout House today. First, I found a shotshell. It was a UMC Co. Club No. 10. This shot shell was made between 1865 and 1911. There is a row of houses within 50 feet of where I found it and the earliest house there was built in 1900, sooooo I am guessing that the shotshell got dropped sometime before 1900.
Then I hunted for a while with nothing much to show for until I got a mid-tone at seven inches deep. The signal turned out to be an old copper or brass child’s ring. It’s somewhat bent out of shape but I can tell that the top is shaped like a flower. The stone is missing. I surmise that this ring was dropped by a Girl Scout sometime during the time the Girl Scouts used the building, which was from the mid 1920’s to around the early 80’s.
Judging by the material the ring is made of, the style of the ring, and the depth at which I found it, I would say this ring was dropped a long time ago.
Copper child's ring
The history of this spot in the park is rather interesting. Back in 1917, a clinic for sick babies was built there. It was called the Fresh Air Baby Hospital because, sick babies were shuttled from Wesley Hospital to this site so that the babies could spend a few hours breathing the fresh air of the park. The clinic only operated during the daytime hours and in 1920, it caught fire one night and burned to the ground (no one was there at the time). A new clinic was built 200 feet West of the old building and the new clinic operated until the mid ’20s, when Wesley built a unit at the hospital where the babies could get fresh air at all times of the day or night.
So the building at the park was passed on to the Girl Scouts of America. I have found other custom rings there. Plus I found a brownie pin as well. I am betting that there are old silver and copper coins there too.
Thank you for looking!
The Dirt Is Good To Me 
this is Bacardi off of the friendly forum. My son and I hit the girl scout building a few weeks ago with little luck. Ear ring and a few pennies. Went into those woods across the street to scout, and our under growth is too thick compared to what you see those guys further up north swing in (treasurefeind, lookn4seated, DD). Saw last night Redd posted finding a ring in there though. Cool all the history that you had researched. Went to Riverside in 2nd and 3rd grade, and can remember hearing some of it. Please contact me on your next group hunt in hopes that I can catch up with you guys. Surprised that we have so many MDrs in the area.