So it's April Fool's Day today. April 1st is the day of the year that we call April Fool's Day. And April Fool's Day is a day where you play tricks on people and then when they realize it's a trick or even when they don't realize it you yell, "April Fools!" One of the tricks that teachers sometimes do on April Fool's Day is when their students walk into class they say, "I hope everybody's ready for the test today." and then the students get a little bit stressed because no one knew there was a test that day. It works best if you actually have a stack of fake tests ready to go and then you say, "Everyone has 5 minutes to study and we'll start the test." And then you let them kind of whisper to each other, "What's the test on? I didn't know there was a test." And then after most of them are sufficiently stressed you yell, "April Fools!"