To change rosters: **If you change a grade level you also need to remove them from their current roster and add to the new one.
Within Dashboard go to Teams
Click the event
Find the team and click "Edit Roster"
Find player and select "remove" (this will put the player in the "available player que")
Go back to the manage teams home page and select the team you want to add the player to
The player will now be at the top under "available players"
Click "add to roster"