Dinner is an often used running gag. All the meals in the series take the form of nondescript green blobs which are possible vegetables. Calvin usually hates what his mom prepares. He often makes comments on the meal, such as "This looks like bat barf." He occasionally orders pizza secretly. He often sees his meal as alive, at some points singing or eating Calvin. Many times, Calvin reacts to the food by choking, spewing it out, and acting as if it were poisoning him. In order to make their son eat, Calvin's parents usually tell him that it's something gross, like stewed monkey heads, maggots, or spider pie.
Calvin once pretended that the food was disgusting, as shown once when he got sick from swallowing it, yet ate it normally after discovering it was hamburger casserole. This may show that sometimes Calvin is used to reacting after swallowing it.
Calvin also pictures how his mom's cooking, and in strip it is seen as Calvin's mom stuffs in a squid, and adds diesel gasoline, and drops an unknown head. Next, his mom pours paint and blends it to green slime. Once, Calvin imagined there was a plate with a big pile of green stuff that trapped Calvin and ate him then burped out Calvin's skull and one of his bones. After that, Calvin's parents danced together. Then, at the end, back in the real world, Calvin said, "You're trying to kill me with this stuff, aren't you?! Just admit it!!"