Theory, Practice and Destructive Properties: Liar, Liar by Gary Paulsen
 
Fourteen-year-old Kevin is one of the best liars out there, but he doesn't think it's a problem. It's not like he means to cause trouble by lying all the time; he just tells lies to make things easier for everyone...and, okay, maybe for himself as well.
Like telling his social studies project partner that he has a serious disease so she'll do all the work. Or lying to his teachers to get out of class so he can spend time with his crush.
But as his lies start to snowball, Kevin's friends, family, and teachers aren't very happy with him at all. Now he just might have to do the unthinkable: tell the truth.
 
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