Calvinball is a game in which the rules change every time it's played, or, whenever Calvin damn well pleases.

While wearing masks: [link]

What does Calvinball mean? I know what it is, but the two times I've seen it used, it didn't make sense to me in context. Is it meaning a game whose rules are made up on the fly?

Pretty much, yeah -- when Calvinball was played in C&H strips, it wasn't just that the rules were made up and subject to change on a whim, but also seemingly illogical, over the top, or just silly.

(And the best way to get cricket if you're from the non-cricketing zone is either Laagan or C. L. R. James. It becomes a game with mandatory breaks for singing and dancing or class struggle, respectively.)

Calvinball, according to Wikipedia

Calvinball is a game played almost exclusively by Calvin and Hobbes as a rebellion against organized team sports (like baseball), although the babysitter Rosalyn plays on one occasion. Participants of Calvinball wear masks; when asked why, Calvin replies that "no one is allowed to question the masks." The rules of the game, besides that a soccer ball and wickets are almost always used, are invented as they go along, but one consistent rule is that the rules can never be the same twice (which in itself is a self-denying paradox). Either player may change any rule at any time, so the only way to break the rules is by using one rule twice. Scoring is also entirely arbitrary: Hobbes has reported scores of "Q to 12" and "oogy to boogy." Calvinball is essentially a game of wits and creativity, rather than purely physical feats. However, it's a running joke that Hobbes is typically more successful at the game than Calvin himself. Calvinball could be described as a Nomic game, and thus bears a similarity to others such as Mornington Crescent and Stanley Random Chess.

Laagan

Nuh-uh -- they fade to a training montage right when the rules are being explained! (E and I had to pause the DVD and go here before we watched the rest of the movie.) And even then, there are sentences like:

When all the batsmen are out, the team is all out, apart from one batsman who is not out.

Which leads one to believe that it's all an elaborate excuse for tea and sandwiches after all.

Mornington Crescent. That always confused me.

sigh. I miss Calvin and Hobbes.

yeah, me too. The wiki entry on Calvin and Hobbes is actually pretty interesting. And made me a little nostalgic.

I've read the "Q to 12" one!

t runs off to search for a boy and his tiger

Calvinball is a game in which the rules change every time it's played, or, whenever Calvin damn well pleases.

While wearing masks.

With tigers.

Calvinball could be described as a Nomic game, and thus bears a similarity to others such as Mornington Crescent and Stanley Random Chess.

Great entry, but I'm sad they didn't mention Royal Fizzbin.