i would suggest if they are little kids to make a circle and have everyone tell there names and then to have them each do a dance move. haha idk. and introduce yourself.
then i would suggest to start a warm up that you would repeat and add onto every class.
then you could do some fun isolations and teach a quick routine.
and if you have time put some fun music on and do an improvisation thing for fun.
idk if this helps but good luck!!