First day of class at Hogwarts

A group of first-year students walked into a classroom at Hogwarts School of Witchcraft and Wizardry. The professor, Febuina Pell, was young for her profession and had never married, but was well respected and had written the very textbook to be used in the class. One of the students, a muggle-born child, gazed in awe at the chalk dancing across the board as it spelled out the professor's name. As they began the lesson, the muggle-born student struggled with one of the spells. He was reading it straight from his second-hand book, but his wand just wasn't responding as it should. It would spew yellow flames in all directions, repeatedly striking the bells in the tall clock in the corner or even landing in the ink wells on the desks, sizzling as the flames sputtered out. After searing his eyebrows for the 3rd time, he raised his hand for the professor to come over and help him. She looks over his shoulder, sees the writing in his book, and immediately recognizes the issue. The previous owner had spilled some tea on the pages and had attempted to re-write some of the words where the ink had faded. The result? Miss Pell's spell was misspelled, causing a mis-spell from hell for the bells and the wells.