I’ve already seen a few mentions of the day of practical jokes, but there are three variations of the spelling.
1. April Fools Day
2. April Fool’s Day
3. April Fools’ Day
It doesn’t look like Google even cares about the placement of the apostrophe and if there isn’t one, the results are only slightly different.
I hope the war doesn’t dampen funny people’s desire to make others chuckle, because gosh darn it, I want to chuckle.