You can go online and check out all the schedules and or cancellations that the metro parks list on their website. Most classes meet at the park's central building located just a short walk from the parking lot.
Enter the park. Turn left at the first split and veer right at the second to get to the central house. There is a standing white flip sign at the entrance that has the events and classes for the day on it. If you can't check online look at that sign.
The central house usually...check the website if not sure...
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