Lightweights

"Weak people exercise to become stronger - but dumb people seldom study to become smarter.", I said to a young cousin more concerned with football than grades.
As I had him do a full workout with extremely light weights, "What's the point?", he asked.
But they always listen to what I say and often do what I tell them to do.
After the workout, "That was a waste of time and didn't do any good.", he said.
"This is the same way you approach schoolwork.", I said.
"Oh, dumb people are too dumb to study....", he said.