The Allison Wonderland

Here's a whole different thought: 

The Sam Morgan Trail goes from Battle Creek to Hidden Falls.  While riding that trail, you would see the Indian Mounds, limestone cliffs, Fountain cave sign (a ride through time?)  You’d pass grain elevators that was mentioned in an earlier comment as possibly being the stone circles.  You’d end up at Crosby/Hidden Falls on the flood plain.  This is where the Minnesota and Mississippi meet which is muddy.  I found the following comment that might explain springs from mud: Gwen Westerman & Bruce White write in their book "Mni Sota Makoce: The Land of the Dakota": "The place of first creation is at the confluence of the Minnesota and Mississippi rivers, where the Dakota people came from the stars to be on the earth. Two bluffs were formed from the earth, one called Caŝķe Taŋka and the other Caŝķe Cisṭiŋna.  The Earth opened herself in that way, and from the mud the Creator made the first Dakota man and woman."

Maybe the medallion is on the border of the trail in Crosby?

I thought of the Como "rings" we called them. We met at one the 3 "rings" often and had fires there and it popped in immediately. I also saw the word "ride" and there are the rides there. Behind the rings is what we call Como 3, its a ball field in the woods, kinda hidden back there, where as the softball fields down the street from the rings are right out in the open. I do not believe that there is a hockey rink anywhere. Past - Its been there many times in the past. There is a high point in Como that over looks the lake, but no where near the rings, but the hidden ball field is elevated much higher than the rings and is surrounded by trees on 3 sides, they are not pine trees but there are pines in other areas of the park obviously. Como Park itself is not on the Border per-say. But being that Como is such a big park, if it were hidden on the border edge of the Park, that would be a very large area to search.

The survivors of "the flood" did so via a 40-day "ride" on a boat - an ark. 
I think this clue is listing several landmark objects that visitors of the park will see either from on their way to the spot where the puck is hidden.

Ride this rhyme:  Hickory Dickery DOCK!!!

Okay.  Another potentially dumb idea.  One of the buttons depicts building of a snow castle.  Is that a thing?  Or is that a mis-reference to Ice Palace?  I don't see snow castle building among the SPWC activities.  Of course, I do now see the Scavenger Hunts!  I'm such an idiot sometimes... 

Roundabouts are stone circles maybe

Now I'm embarrassed!  No disrespect, David.  Please forgive my ignorance.  Clearly I am the one who's not familiar enough with SPWC activities. I thought I had that "buttons" reference figured out.  Now I'm puzzled...

If you feel you can trust the search feature on Google Maps, then I would say no to a road named Stone Circle.

Is there a stone circle road?

Since someone mentioned it, and now I realize I forgot to mention it here, let me tell you all about the Winter Carnival Scavenger Hunts! I know you're all busy looking for a medallion worth $10,000, but perhaps you'll want a break from that. Or maybe you'll want something else to do once the Medallion Hunt is over. The Scavenger Hunts start today at 5pm and run through next Sunday at 5pm. They are all run through the Goosechase App. There are four different hunts to choose from, each with a different flavor:

North Wind Hunt - This one is like 30 mini one-clue treasure hunts. You'll get 30 clues, each leading to a location of interest in St. Paul. There are parks, historic locations, unique businesses and more. Once you have figured out a location, you go there and either take a picture of something specific or submit your GPS coordinates, depending on the mission.

West Wind Hunt - This one is for the whole family. There are 15 missions and each one directs you to a different location in Como Park. The adults can figure out the clues to the locations. Then head over there and let the kids look for one of the West Wind's horses who will have a riddle (aimed at kids) as to what the horse's name is. Enter the name into the app and the mission is complete!

East Wind Hunt - Your team has nine days to solve ten puzzles that range from difficult to diabolical. When (if?) you solve a puzzle, it will lead you to a specific location in St. Paul. The mission will direct you to a sign which in turn will give you a single letter. If you can get through all 10 puzzles, the 10 letters you accumulate will unscramble to give you the final location. Submit a picture of the final object at that location and you've completed the hunt!

South Wind Hunt - A more traditional scavenger hunt. Unlike the others that all direct you to specific locations, this hunt is looking for specific items and activities, wherever you may find them. The thing they all have in common is that they are about having fun in the winter time.

Each hunt does have a $20 registration fee (which helps support the Carnival). You can officially have up to 4 people on a team (though you can consult with as many as you like). The first team to finish each of the four hunts will be invited to march in the Torchlight Parade. Also any team that finishes all the missions in a hunt will get a small prize. Get more details and register at https://www.wintercarnival.com/events/saint-paul-scavenger-hunt/

I'm with you on this one kind of throwing me off. I thought ride this rhyme = street car line but that still doesn't narrow down to one park. 

Stone circles maybe are grain silos on east 7th, saying it's literal

This clue really reinforces my belief in which park is THE ONE.  I'm sure you're already in the habit of doing this, but be sure to look through the photos posted for parks of interest to you. 

Yea, the Scavenger Hunts for the Winter Carnival are an actual thing. Trust me, I have an intimate knowledge of them. lol Which makes for a good segue...

It seems like no one really knows what to make of this clue in that there's been little to no discussion about it on any of the message boards. Or maybe everyone has figured it out and just isn't sharing! Probably not.
Certainly there is an inclination to take something like "stone circles" and apply it literally. That would give you Como, Crosby, Hidden Falls, Newell, and Swede Hollow off the top of my head. Yet it strikes me as unlikely that the true meaning of this (or any) clue would be so clear. It sounds more like something to divert hunters by giving them a shiny object to distract them.
The first line suggests this is some kind of history clue. Could be local history. A flood sounds like a specific event, though along the river there have been many floods. I think there was a specific flood that finally did in the village of Lilydale. I've been leaning towards New Brighton, and it could maybe fit the history of Brighton England. 
A raised elevation could certainly suggest Highland. This one is general enough that it might actually be literal. 
The last line...Hard to say because I wouldn't say it's even a true statement. It sounds more like a nonsense statement that is either an anagram or just meant to get a specific word or two into the clue. According to the Urban Dictionary, the phrase could mean that we all come from the street or we all come from nothing. I'm still not sure where that would get you. Looking up "mudspring" got me to a Dr. Mudspringer who sells motorcycle parts (ride?) located in Moundsview. There are a couple of nearby parks, but they didn't seem promising offhand.
David B. Allison

The Winter Carnival has their own scavenger hunt.  The Pioneer Press has the treasure/medallion hunt.

Clue 6 First thought is fire pits at como

This is NOT a button.  It's the official logo of the Hunt.  Note the word "TREASURE." Now I'm thinking this is at least partly why that word was used repeatedly in the early clues.  I still think "Treasure" is a reference to the name of the actual park.

The fact that you sent that here is pretty funny given who runs the scavenger hunt haha.
It’s a different event - run by the proprietor of this very group.

One of the SPWC buttons says "Scavenger Hunt" on it.  Either this is an error or a cue to the medallion being something other what we've come to expect it to look like.  I'm leaning toward an error made by someone not familiar enough with the SPWC activities.  A scavenger hunt usually involves locating a number of items rather than just one, doesn't it?