Thanks for writing. Unfortunately, there's not really anything you can do. But fortunately, the mushrooms are improving your garden by breaking down organic matter and enriching your soil.
If the mushrooms really bother you, the best thing I can suggest is breaking them off by raking them up when you first see them start to appear. Also: Many mushrooms do best in moist conditions, so if you water your yard, cutting back on the amount of moisture you use may help.
---Justin, Senior Garden Editor, BHG.com