1 Book Found

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"Main character is a kid, goes to school. His father has a restaurant. It’s financially back up by a rich old who is mean. Main character has to go the rich dude, believe to aid him for something. Anyways, main character has to make a project with a kid. Dust bowl is involved when he goes over. The kid is weird, seen making a tombstone. Makes unsual references. Mentions later on the story of having a terminal illness. Main character supports via a concept of giving the weird kid a piece of his life time thru a paper. There’s no supernatural involved nor any fantasies. Whole school gets involved. Is supportive. Climax is finding out the illness is fake. The main character dad had a stroke near the end of the book. Took place at the school where the people held an event for the kid"