Michael's has classes, you would have to call or stop by and look at calendar. Joann's Fabrics too, I think.
You can check the calendar of monthly classes.
Each location probably has a different schedule, depending on who they get to teach the class. Call the individual store that you would like to go to, to take the class and ask for the schedule. If they aren't having a cake decorating class anytime soon, you might be referred to another store that is having one.
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