A story arc that lasted from the 10th to the 29th of September in 1990.
It starts off with Hobbes "helping" Calvin with his math homework. When Calvin's mom sees him reading comic books, Calvin claims that he's all done with his homework and that he's doing just fine in class. Calvin's mom then leaves to go to a parent-teacher conference with Miss Wormwood, which of course freaks out Calvin and makes him nervous about what Miss Wormwood will tell his mom (and what his mom will tell his dad).
After Calvin's mom gets home from her meeting with Miss Wormwood, she admits to her husband that it didn't go so well and they talk about what Miss Wormwood had said. After that, Calvin's parents talk to him about what Miss Wormwood had told them: Calvin's not doing so well in class and Miss Wormwood feels that Calvin needs to start putting more effort into his schoolwork, particularly when it comes to math. Deciding that Calvin needs to start spending more time on his homework, the first thing that happens is Dad comes up to Calvin to help him with some math homework, but Calvin's very resistant to it. Calvin argues that learning math is totally irrelevant and that he can get along just fine without it, but his dad points out that almost all jobs require some form of math -- to try and get Calvin more motivated, his dad uses pennies to teach him some basic addition and subtraction. Later on, he claims to his wife that it seemed to make Calvin more excited to learn math.
The next time that Calvin's in school, he's much more confident in his math skills (probably too confident). In fact, when Miss Wormwood hands out sheets for a math quiz, he gets very excited about it and makes a bet with Susie Derkins: whomever of the two of them gets a higher score on the quiz has to give the other a quarter. At first, Calvin's confident that he'll do great on the quiz and win his bet with Susie, but he gets stuck on the first problem ("6+5=___") and then gets lost in a Spaceman Spiff-fantasy. By the time he finally answers the first question (which he gets wrong), time's already up for the quiz -- Calvin, now freaking out and rushing to finish his quiz, guesses on the rest of the questions before finally handing it in to his teacher.
Calvin, predictably, flunks the quiz while Susie, not surprisingly, does much better -- in fact, Susie gets a perfect score on the quiz. Later that day, while talking to Hobbes about what happened, Calvin tries justifying what happened by claiming that the only reason he flunked was because he ran out of time. Also, since Calvin lost his bet with Susie, he had to pay her 25¢ -- but Calvin then claims that he "cheated" Susie by "only" giving her three dimes (which is 30¢, obviously worth more than a quarter) instead. Hearing this, even Hobbes points out that Calvin needs to get more serious about improving his math skills.
- When Calvin was making his bet with Susie, he suggested doubling it, which he thought was 35¢ (the correct answer would've been 50¢).
- The correct answer to the first question of Calvin and Susie's math quiz would be 11 -- Calvin's answer was "6+5=6."