Pencils are a new feature of High School Story. They are used to complete mini games and quizzes in the library. Pencils regenerate twice a day, or you can purchase them through the store. When you obtain the library, you are given 40 free pencils. After completing 31 Extra Credit mini games using pencils, you unlock the character Kallie, a writer girl, but you must first complete the total of 99 Extra Credit mini games before she appears in your administrators office. Pencils are used to unlock different levels of the Extra credit.
in extra credit the Mc helps a girl named Kallie, who was homeschooled and didn't know much about high school. In other words she is a childish girl.