The children arrived by car and not Hogwarts Express, ushered in by parents instead of Thestral-drawn carriages, but once they entered the school of witchcraft and wizardry – which appears to unsuspecting Muggles to be simply an activity room at the Elkridge branch of the Howard County Public Library – they were greeted by a witch just the same.

Draped in a floor-length, forest-green cloak and a black hat emblazoned with gold stars, Deborah Bosilovich, a teen instructor at the Elkridge branch who preferred the title of "Professor," surveyed her new pupils, a group of tweens aged 9 to 12, the age range at which magical skills start to become apparent.

The first thing to do, she announced, was to make quills. These would be essential for notetaking as the students discovered the ancient secrets of the wizarding world, from the wand-work of Charms class to the specifics of dragon taxonomy taught in Care of Magical Creatures.

The classes were just some of the activities planned for Hogwarts Summer School, a weeklong program held at the library for Howard County's aspiring young witches and wizards.

Over four days beginning July 28, Bosilovich has been hosting two-hour sessions of magic-themed activities: crafting papier-mache dragon eggs, searching for Quidditch balls hidden in the children's section of the library and even a Quad-Wizard tournament – a variation on the Tri-Wizard tournament from the wildly popular Harry Potter series, written by British author J.K. Rowling, which expands the pool of participants to make room for a representative from each one of Hogwarts' four houses: Gryffindor, Slytherin, Hufflepuff and Ravenclaw.

But first, the students had to be sorted. As every devoted Harry Potter fan knows, each one of Hogwarts' incoming first years is placed in a house by the wizened Sorting Hat, which takes into account the personality and temperament of its wearer before making a decision.

The most coveted placement was Gryffindor, the house of Harry Potter – "The Boy Who Lived" – and his fearless friends, Ron Weasley and Hermione Granger.

Susie Park, 11, donned a red-and-yellow shirt – Gryffindor's colors – in the hopes of landing a spot in her favorite house. It worked.

"I was nervous," she said after learning her placement: "I wanted to be in Gryffindor." The house has a positive association in her mind, she said, because "it's for the brave."

Her fellow Gryffindors agreed. Would any other house do? They shook their heads no. It was Gryffindor or bust.

But at the other end of the room, the Slytherins said they were happy with their placement, too.

"I'm more of a Ravenclaw than a Slytherin," said 12-year-old Marissa Scharf. But, she added, "being in Slytherin doesn't mean you're evil. It just means you're ambitious and resourceful. I think it's just an honor to be invited to Hogwarts."

Katherine Thomas, 10, was excited for class to begin. Like Hermione Granger, the self-proclaimed Harry Potter fan came to Hogwarts with a wealth of magical information on the tip of her tongue.

Like Hermione Granger, she was already familiar with the charm to make objects levitate.

"Wingardium leviosa," she whispered under her breath as soon as Professor Bosilovich broached the topic.

Then the professor asked the room to name the charm. Katherine's hand shot up.

"Wingardium leviosa," she said, demonstrating the proper charm-casting form with a precise swish and flick of the wrist.

"But" – she stressed this important detail – "it's pronounced wingardium levi-ooo-sa, not wingardium levio-saa."

Bosilovich nodded. At Hogwarts camp, the spell worked like a charm.