On Tuesday morning, when no one is awake, take come cereal, chew it up, and spit it out in your toilet DONT FLUSH. It will look like vomit. In the morning, tell your folks that you threw up in the toilet, and you feel that it will happen again, and you don't want to risk it happening in school. Also, if you temp. is over 100, they usually won't let you into school if you call them and ask if its okay for them.