This year, I began teaching a recorder class to third graders. I have no general music or recorder background. In a panic the first week I came up with this "Recorder Rap":

Sleeping recorder, lift it nice and slow
Left hand at the top, right hand below
to-toto to-to_to-to [kids speak the shave and a haircut rhythm]
Now we're in ready position, get set and blow!
to-toto to-to_to-to [kids blow the shave and a haircut rhythm]

It isn't the best rhyming scheme, but it does seem to help with reinforcing:

• "sleeping position" where recorders are on the floor in front of the kids
• "ready position" with hands and instrument in place but no noise
• making a "to" noise with their mouths before they actually blow the "to"s in rhythm.