In The Happiness Project, I write about one of my favorite resolutions — to celebrate minor holidays — and Elizabeth and I have also talked about this a few times on the Happier podcast. I’ve been gratified to hear that many people also have fun celebrating these little, colorful-yet-not-much-work occasions. (I love it when people send me photos.)

Today is April Fool’s Day, and I played a trick on my daughters (my husband is traveling for work). It’s a Saturday, and they’ve been on spring break, so I went into their rooms at the time when I wake them up on school days, and went through the whole morning routine as if it were Monday morning.

For a few minutes, I managed to fool them in their grogginess, but pretty quickly they realized what I was up to.

Reflecting on my last few years of April Fool’s Day pranks, I’ve learned something about myself: I do better with a sight gag, like the time I dyed the milk in the carton bright green, and then poured it over my daughter’s cereal (see image), than I do when I’m misleading them. I’m a terrible liar and can’t fool them for long.

I love these kind of easy, fun traditions. They build happiness because they mark the passage of time in a special way, they’re memorable, they’re light-hearted, they contribute to a sense of group identity.