Being a parent myself I think I know pretty well how Calvins parents must feel sometimes. Sometimes I catch myself thinking "That's something Calvin would do!" when my kids perform some of their crazy stunds or comes up with weird ideas.
This is what Bill himself has to say about Calvins parents:
I've never given Calvin's parents names, because as far as the strip is concerned, they are important only as Calvin's mom and dad. Calvin's dad has been rumored to be a self-portrait. All my characters are half me, so it's true in some ways, but Calvin's dad is also partly a satire of my own father. Any strip about how suffering "builds character" is usually a verbatim transcript of my dad's explanations for why we were all freezing, exhausted, hungry and lost on camping trips. These things are a lot funnier after 25 years have passed.
Calvin's mom is the daily disciplinarian, a job that taxes her sanity, so I think we get to see her at her best. I regret that the strip mostly shows her impatient side, but I try to hint at other aspects of her personality and her interests by what she's doing when Calvin barges in. . . .
. . . As secondary characters, I've tried to keep Calvin's parents realistic, with a reasonable sense of humor about having a kid like Calvin. I think they do a better job than I would.