Jake Drake, Class Clown by Andrew Clements

Jake Drake really likes school. In fact, he considers it his job - a full-time job, of course - and his teachers are his bosses. He's had some really great bosses over the years, and one boss who wasn't actually great really, but he learned a lot from her!

During Jake's second grade year, Miss Bruce came to teach his class. Miss Bruce was a student teacher - that means she was still in school, studying to be a teacher, and she was practicing with Jake's class. But there was one other thing that made Miss Bruce different from any of Jake's other teachers: Miss Bruce never smiled! She never smiled, she never laughed - she never even grinned!

But one day, entirely by mistake, Jake learns that Miss Bruce does smile - and even giggle! And he makes a life-changing decision: he's going to help her smile during class. And how is he going to do that? By becoming the class clown, of course!