The band is learning to play in tune in the second book of this laugh out loud series starring four musical instruments in their first year at Band Camp!

Cordelia is feeling down after losing her footing during the tug-of-war competition, so Kaylee, Zook, and Trey decide to throw her a surprise birthday party. Determined not to disappoint her friends again for the next challenge, a group hike, Cordelia does all she can to prepare, but all the rest of the instruments' secret planning for the party is making Cordelia feel even more left out. Who will end up surprising who when the day of the hike comes around?