This strip was originally published in the newspapers on December 1, 1989.
Mom is talking to Calvin, but he's thinking about getting another "discussion" about his study habits and the importance of homework. Calvin continues thinking about how he tried to tell her it's hard to study when one's size suddenly starts increasing. Mom is still talking and gesturing, but Calvin continues thinking about how she says it's all his fault. Mom hasn't been as big as a galaxy, so she doesn't understand how anyone else can be. Calvin thinks Mom is wrapping up, so he starts nodding. Mom tells him she's glad they had this little talk.
This strip was also published in the following books:
Scientific Progress Goes 'Boink' on page 37
The Indispensable Calvin and Hobbes on page 165
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