This is an excerpt from Assessments and Activities for Teaching Swimming eBook by Monica Lepore,Luis Columna & Lauren Friedlander Lizner.
Skill 5.1 - Front Crawl for 12 Yards With Rhythmic Breathing, High Elbows, and Body Roll
The student starts in waist- or chest-deep water at the wall with 12 yards of clear space in front of him.
Demonstrate the "catch up" arm motion of gliding off the wall with one hand on top of the other and arms extended. Using the flutter kick and the front crawl arm motions, stroke with one arm (with a high elbow and body roll) and touch the hand of the other arm before beginning to stroke with that arm. Have the student perform this stroke, and provide feedback when necessary.
The student swims 12 yards using the flutter kick and a "catch up" front crawl arm motion while breathing to the side. He alternates arms using high elbows and body roll and keeps one arm out straight while stroking normally with the other. The student may not move the extended arm to pull normally until the other arm comes back to the starting position and taps the waiting hand.
In the Catch Up activity, the swimmer (a) performs a one-arm front crawl and then (b) catches the other hand before the next one-arm stroke.
Learn more about Assessments and Activities for Teaching Swimming.