Because all of your teams are variables, just unset them.
/unset %team*
Keep in mind that if you have any other variables starting with %team from your script or someone else's, it will also remove those. As such, it's always best to make unique variable names that are unlikely to conflict with other scripts. Something like %scriptname.team1 or %jackerandall.team1 or something that will not likely be used by anyone else in a script. Remember people tend to use multiple scripts by multiple authors.
