Open enrollment is only a thing between school districts. Someone from Hopkins for example enrolling into Minnetonka. Open enrollment from outside a district can only be closed if the schools are deemed to be full. Wayzata is a case of this.
Intra-district school choice is an entirely different matter and is up to the district. From what I know, the Osseo district does NOT allow kids outside the attendance boundary to enroll into Maple Grove, and the Anoka-Hennepin district does NOT allow kids outside the attendance boundary to enroll into Andover. Those two obviously being the wealthiest of the multiple high schools in each district. Not positive, but I think the same is true for Armstrong and Cooper.
I've written about this before, but as the Maple Grove side of the district continues to grow, they're going to end up having to shift attendance boundaries where families who thought their kids would go to MG will shift to Osseo, and Osseo families to Park Center, and that's going to be a very ugly discussion.