What is a Pacer?

Attributions: 
Story and photo by Alec Carlson

Yesterday, we ran the Pacer test in our P.E. classes.
For those that don't know what the Pacer is, it is a 20-meter, multistage, aerobic capacity test that progressively get more difficult as it continues.
All the students did great but these few were the top ones of their classes.