Tis the season for beginning recorders in 3rd grade at my school...squeaks to send home for parents to enjoy all vacation long!
When first introducing recorders, I've always had students struggle to play with their left hands on top. Thus, I am up with my "left-hand-bands."
During the first few weeks of playing recorders, I have students get their recorders and a band. They wear it on their left hand all the time, and it helps them to see if they have the correct hand on top. It also helps me quickly check that they all have their left hand on top.
I found these cute bands at Party City a few years ago, and I now have a tub full to use. The kids get a kick out of wearing them too.