Nothing like waiting until the last minute, but I came across a few cute ideas for April Fools' Day. Family Fun has some really cute meal ideas. Why not confuse the kids & serve them "dessert" first or give them the main course that is actually dessert. I have not decided what I am going to do yet! You should also check out Allrecipes. They have some other great food prank ideas. I hope that you have fun!!
Some of my favorites:
Magic Milk Bowl...I think the kids would LOVE this!!