The Volunteer

 New assistant coach Stormy Flare thinks some of the girls are slacking during practice, so she calls them in for a little "motivation". As team captain (and Stormy's daughter), Spitfire has to wait until last, as an object lesson in what letting down the team means. And she knows from experience that misbehaving backsides get worn out long before her mom's arm ever does!

Additional tags: school, Equestria Girls, arm pinned