Well, the nice thing about Rules Practice is that it can be done anywhere, and they don't really need you in order to serve it.
So.. if you can't be in your classroom, you can pull them aside anywhere to do it, blacktop/field, playground, cafeteria, etc... -- in fact, that's GREAT because who the heck wants to sit and gesture/repeat a rule for THREE MINUTES IN FRONT OF THEIR PEERS??? No one.
And... if you ARE in your room but you need that planning time, no biggie -- set a timer, and leave the instructions on the overhead or the board. Inform them that if they don't do it correctly, you start the timer over. Then they do their practice while you do your work, and they're gone in 3 (maybe 5 if allowing for start-overs) minutes, leaving you to do your stuff.
There's got to be SOME time in your day, every day, that students do not want to give up-- even 3 minutes. (and if there's not... well... change that! Every class needs something to look forward to

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