Using a kickboard, have your swimmers do 25’s or short distances (from the wall to 1/2 way).
Start in position 11, holding the bottom of the board.
Breathe: take a breath.
Put your head back in the water.
Kick: do a breaststroke kick.
Glide: using the strength of the BR kick glide through the water before starting again.
I got this drill from the ASCA Level 2 class where they talk about “Up, kick, glide” but I like substituting “breathe” instead.