Am I missing something here? It is literally called gym class. And the room where it’s happening is called the gym.
Related
4 Comments
Yes, but he is just getting back to school and has forgotten about this, or for some reason hadn’t previously experienced it. Meanwhile, while stuck at home, his parents obsessed over gym memberships and whether they could use them.
Grownups have to buy a gym membership : they go to the gym because they want to, or because they can’t get a refund.
The kid hates gym, so the only reason to attend would be not to lose his money. Hence his comment.
The joke is that the kid is behaving like a grownup. He’s actually here because gym is a mandatory school activity.
Kids saying grown-up things.
Could it be his first time in gym class and he knows that his parents have gym memberships?
Comics I Don't Understand 
Yes, but he is just getting back to school and has forgotten about this, or for some reason hadn’t previously experienced it. Meanwhile, while stuck at home, his parents obsessed over gym memberships and whether they could use them.
Grownups have to buy a gym membership : they go to the gym because they want to, or because they can’t get a refund.
The kid hates gym, so the only reason to attend would be not to lose his money. Hence his comment.
The joke is that the kid is behaving like a grownup. He’s actually here because gym is a mandatory school activity.
Kids saying grown-up things.
Could it be his first time in gym class and he knows that his parents have gym memberships?