We added this question and answer to our FAQ:
How do I turn off "Don't forget your upcoming events!" emails?
SportsEngine (who makes the software that runs our website) has added a new feature that sends notification emails for team practices and games. Unfortunately they have not (yet) given us the ability to turn them off. Each parent or team manager must do this individually. Also unfortunately, they do not have a help page that explains how to do this. We're told for now that the best way to contact SportsEngine for instructions on turning these emails off is via online chat: go to their Contact Us page (https://help.sportsengine.com/customer/portal/emails/new) and click the START LIVE CHAT button. As soon as anything changes we will post an update.