“Magi, I believe you had better start explaining yourself,” Principal Towne said almost in a whisper, his lips barely moving.

“Of course, Principal,” said Mr. Corntassel. “You see—and I know you disapprove of gambling, Athansius, but please hear me out—Jacob and I had placed a small wager on the outcome of Saturday’s Quodpot game. The winner would cover three lessons with the loser’s most incorrigible, most exasperating class. Well, though they distinguished themselves by their superb flying and their unparalleled sportsmanship, Proudfeather lost.”

“We all know that!” Mr. Malleus spat.

“And I agreed that I would teach three lessons to the class of Mr. Malleus’s choosing.” Now all eyes fell upon Will, Kate, and Dana. “Second-year Proudfeathers and Fairgarlands. The very definition of ‘incorrigible’ and ‘exasperating,’ wouldn’t you say?”

Madame Glapion joined in Mr. Corntassel’s grin. Mr. Malleus and Principal Towne remained grim-faced. Neville just stood there, mouth agape.

“Then I realized that neither of us had clearly stated when these lessons were to take place. So I figured, No time like the present!”

“So are you saying, Magi, that you put these children up to breaking into Mr. Malleus’s office?” said Principal Towne, his volume rising ever so slightly.

“Not at all, Athanasius. I’m saying that, like all forms of magic, Defense against the Dark Arts involves a bit of detective work. You see something suspicious—a prematurely exploding Quod, for example—what do you make of it? Is it worth investigating or not?

“Magi, you didn’t sabotage that Quod? Someone could have been hurt!”

“Now, now, Justine, I’d never do anything of the sort. I was still hoping for a Proudfeather comeback! You always get an unpredictable Quod now and then. We all know that. But you should have heard the Proudfeather fans walking back to the dormitories. They were convinced someone was up to no good. I thought, ‘Here’s a teachable moment if there ever was one.’ A defective Quod by itself is an accident. But add some strange noises in the Proudfeather common room, a scrap of parchment with a coded message falling into the hands of an overly suspicious Fairgarland—” (Dana blushed at this statement) “—a mysterious cloaked figure prowling the grounds…”

“I never heard anything about a stranger on campus!” Mr. Malleus interjected.

“I made sure the intruder was only seen by second-year Proudfeathers and Fairgarlands. It’s their lesson, after all. I, uh, arranged for her to be seen departing from certain rooms a few moments after you did, Jacob, or else to skulk around outside your office when I knew the right students would be passing by.”

“Her?” Mr. Malleus started.

“By the way, Athanasius, my sister is in town and we’d like you to be our guest Christmas Eve if you don’t have other plans.” Mr. Corntassel paused to reclaim his line of thought. “They’d have never come to you, Jacob, they figured you were in on it!.”

“And we fell for it,” Will said, dejected.

“You pieced together the clues I left you, Will, and you did so correctly to the best of your knowledge. None of your classmates did, though they had the same opportunities—I’d take that into consideration when grading this assignment, Jacob.” He turned back to the three. “Your only fault was in failing to inform a teacher. Confronting Dark wizardry is something best left to adults.” Mr. Corntassel turned to Neville. “Where do these children get the idea that they’re up to fighting monsters?”

Mr. Corntassel crossed his arms. “And that, my friends, was lesson one: Adequate Defense against the Dark Arts requires strong allies. Don’t go it alone if you can help it—especially when you’re only twelve years old!”

By now Madame Glapion was mesmerized. “And lesson two?”

“Lesson two, it turns out, involved only Kate, Dana, and Will, as they were the ones who put my clues together. They can write up a summary of their experience to share with the rest of the class in January. Twelve inches of parchment should do—and, Jacob, I’ll be happy to attend that day’s class and help with the debriefing.

“The second lesson is: Know what you’re getting into. You see, Athanasius, I planted clues pointing to something fishy in Mr. Malleus’s office, but I never gave any hints about what it might be.

“Now, the proper thing to do in a situation like that is to continue to gather information. Research. Books! I’m sure Mr. Malleus has mentioned the concept. You might have discovered some simple techniques of Dark Detection to try. Or perhaps dig deeper into my clues, eliminate possibilities that didn’t match the data. You might have done any number of things. Many of them would have won my praise. Unfortunately, you chose to dive in unprepared. Jacob, I would suggest you take that into consideration as well when grading this assignment.

“I was there at lunch this afternoon when the three of you made plans to investigate Mr. Malleus’s office during the Christmas Banquet. So, as soon as I knew he had finished his day’s work, I hurried down to the root cellar, collected my boggart, and left him here. Oh, and Kate’s Unlocking Charm worked because I didn’t replace all the protective charms on the door when I was finished.”

Principal Towne wore a look of pure bewilderment, half amused and half dismayed.

“Mr. Corntassel,” Kate began, “When we were in Mr. Malleus’s office…. Well, there are an awful lot of Dark Detectors in there. There were a couple of Sneakoscopes and a Secrecy Sensor and a couple of other things I didn’t recognize.”

“Yes?”

“Well, none of them were going off. Wouldn’t they… I mean, how did you….?

“My question exactly, Corntassel,” Mr. Malleus said. “They’d have gone off the minute you picked the lock.”

“And I’m sure I would have, Jacob, if I had done the slightest thing to set them off.”

“If? What do you—?”

“Well, I wasn’t doing anything untrustworthy, was I? I owed you a debt and I was paying it—and promptly at that! What could be more trustworthy? My motivations in entering your office were purely aboveboard. I wasn’t hiding behind Occlumency or any other form of concealment. I wasn’t even invisible. I just opened the door, let in the boggart, and closed it back again. I wasn’t going to steal anything” Mr. Corntassel looked perfectly satisfied with himself. “I was giving you a present—which I had decided to give you days ago.”

Mr. Corntassel winked at Neville and then addressed Principal Towne. “I assure you, sir, that nothing underhanded has taken place here tonight, and I call as witnesses the silence of Mr. Malleus’s own Dark Detectors. But I thought it best for you to hear this story as soon as possible, Principal, before any unfounded rumors get started. I also thought it best for Justine to be here in her capacity as Miss Good’s Head of House.”

“Much obliged,” said Madame Glapion. “But if you don’t mind: You said the bet involved teaching three lessons….?”

“So I did, Justine. Thank you for reminding me.” He glanced at the grandfather clock near the end of the hall. “Jacob, you might want to find a good vantage point to see the covered walkway between the Great Hall and the Proudfeather and Fairgarland dormitories.”

“Yes?” Mr. Malleus said apprehensively.

“In another twenty minutes or so the first- and second-years will have to be in their dorms for curfew. On their way to bed I’m afraid they’re going to have a run-in with a haint—It’s not a very big one, Jacob, so don’t give me that worried expression. I found it tussling with the boggart in the root cellar. You can have it if you want. I just thought you’d like to see how your students handle it.”

Neville and the other teachers returned to the Great Hall in time for dessert. Mr. Malleus joined them some time later, still glaring at Mr. Corntassel. He didn’t say another word to anyone the entire evening and excused himself from the feast at the soonest opportunity. Everyone else seemed to enjoy themselves—even Principal Towne. But the highlight of the evening was when Rufus the ghost floated to the center of the Great Hall and danced the minuet with Annabelle, a pretty young ghost in a flapper dress.

At midnight the rest of the students were run out and the few teachers who had stayed up with them made their way to bed. The hunting trophies had long since drifted off to sleep, and the red-and-green flames in the fireplaces were almost extinguished.

Neville pulled his robes close around his body and lumbered to his guest cottage. Arriving, he magicked fire in this own fireplace and eased himself into an overstuffed chair. After a moment’s thought he grabbed a lap desk and piece of parchment from a side table along with a fresh eagle-feather quill.

Dear Professor McGonagall,

I wonder if you’ve ever given any thought to a more experiential approach to education at Hogwarts….