I always fall for April Fool jokes. Even when I am on the look out for them. When we lived in Scotland, I discovered that the British people love April Fool's Day and not in a small way. They didn't go in for small personal jokes, theirs was on a national scale. The BBC was usually in charge or one of the newspapers and no matter that you knew what day it was, they almost always were able to sneak up on you and pull off outrageous jokes. Quite often they started early, weeks early, setting up the joke.
The best they ever pulled off was the spaghetti shortage in Italy. They showed film of trees, stripped of the spaghetti crop and talked to people all over Italy about how they were coping with the stress of not having enough spaghetti. They talked to botanist and politicians and cooks and people on the street. I can't imagine how much money they spent on this hoax, but come April 1 they had a really good story going that was picked up by the press in other countries and they interviewed people on the streets of London and in the back washes on the islands. No one was immune. The spaghetti famine was genius. People believed it. Right up to the end, when they announced the hoax the next day. It was incredible, but it showed the power of suggestion and the power of the press. Intelligent people bought into it and had a good laugh on themselves for believing such rot. Spaghetti famine indeed!! But it was so believable.
So if you are going to do an April Fool joke, make it good. Spend some time and energy on it and make it worthwhile. I am still working on one, problem is, I have been working on it for a lot of years and haven't got it right yet.