You are a great mother and prepare a good breakfast daily; it is time to give it a twist. If your kids are used to eating their favorite cereal or jam and bread, serve them something completely unexpected. A good idea would be to make fried octopus. Maintain a straight and normal expression while serving it. The kids will make faces and refuse to eat. If you can make them eat some of it, it adds to the humor. After they have eaten some, laugh at them and tell them they have been fooled.
Kids are very possessive about their toys. If there is one thing they can’t stay away from, it’s their favorite teddy bear or doll. When your kids are sleeping, go into their room quietly and pick up all of their favorite toys. When they get up in the morning and are having their cereal, tell them that you have given away their toys to charity. They will have horrified expressions on their faces and will start to protest. When they are done with all the shouting, complaining and protesting, tell them the truth. Laugh at them and say that it was just a joke. They will definitely enjoy it and laugh with you.
If you have kids between the ages of 5 and 10, this prank will really work for them. Kids are used to routines and like sleeping in their own beds. When they are sound asleep, sneak into their rooms and switch their beds (make sure the kids don't wake up when you are moving them from one bed to the other) or the room altogether. When they wake up the next day, they will be surprised and wonder what happened. This way the pranks start right from the time when the day begins. Do not disclose for some time that this was your act until they are really confused and are asking a lot of questions.