Gym Convertors are smart jocks who reward the small guys who tutored them by helping the small guys become big and ripped like the jocks. Then the small guys become, or are converted into, jocks themselves, helping them fit in better with the jocks during high school and college.
An added benefit to this is that the small guys become big guys themselves, and are therefore no longer teased by the big guys, but are accepted by them. The new big guys won't beat up small kids because they were once small kids themselves and they didn't like it when people bugged them.
"Yeah man, don't look so surprised," Andrew told him. "If you help me ace my Physics final, I'll help you get big and ripped like I am! Then you'll never be bullied by anyone again!"
"And I'll be able to fit in better at a big football school if I get an Academic Scholarship to one," Mike realized.
"You'll fit in better here too," Andrew reminded him. "I'll help you become a jock like me, and then you'll be able to sit at the football table with us! And you can come to the gym as well, and work out with us!"
"What are you Andrew, a Gym Convertor?" Steve yelled at him, laughing. "Are you trying to convert every small guy into a jock like us?"
"Naw, just the ones who want to become jocks," Andrew replied. "If they don't want it badly enough, even we won't be able to convert them into jocks like us."