I've walked into the tennis center to try and figure that out myself. There didn't appear to be any sort of office or anything, and the only thing I saw posted by the courts were certain days and times when there are classes or leagues. Almost seemed like the courts are first come first served otherwise, but no way to know for sure.
I didn't realize you had to get permission. I thought it was open to the public, maybe check the information area. If you enter the park across from the high school there is a main center. Where you can pay a membership (it used to be $20, I'm not sure how much it is now)for activities at the park (soccer, hockey) maybe it's for tennis too?
Not sure haven't played tennis there. But maybe there is a sign near the courts. I did see people playing last time I was @ the park.
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