While Shira is anxious and nervous about performing, she still manages to get up and perform with the support of her family and friends. There is a definite trend for showcasing anxiety, but the books are more interesting when the plot focuses more on the characters accomplishing things despite this. The interactions between the cast members are fun, and Paul in particular is a well-drawn character. There are just enough details about putting on a play, and I love that it is based on the author's own experience of being in the Barbershop quartet when she was in school! My school put on The Music Man last year, so it's definitely a play that is still being done!
While it seems unlikely that Monica and her mother would hold such power over the principal, or that Monica would get away with being so mean, this does add a lot more excitement to books, and would probably bother young readers a lot less than it bothers me.
This is another good book about a school play being performed and a good addition to books like Federle's Better Nate Than Ever, Mustaches for Maddie, Freeman's Noah McNicol and the Backstage Ghost, Zadoff's My Life, The Theater, and Other Tragedies, or Young's The Prettiest. (In which The Music Man is also the play being performed!)