Carl was there in the final room, listening to Professor Primeaux's words. He had his quill and parchment out, prepared to take notes, but soon realized that there was no need as the Professor was mainly talking about rules and attitudes. Not that they were not important, though.

When the class was over, Carl dawdled a bit, then decided to stay and practice. He knew he would have many chances in the future to practice the charms, but this time the Professor was present and he would be able to ask questions if he needed help.

After grabbing a box and placing it on his desk, he took out his wand and pointed it at the lock of the box. "Alohomora!" He said clearly and firmly. The box unlocked for him, much to his delight. "Colloportus!" He said this time, but the box remained unlocked. He then heard what the Professor said to a Ravenclaw about concentration and determination. Right.

He tried to block out everybody and everything around him and focused on the box he was trying to lock. Tightening his grip on his wand, he cleared his throat and repeated, "Colloportus." The box locked itself with a satisfying click.