"Thank you," Tate dismissed the girls back to their respective seats. "As you can see, the Protego spell creates a focused shield that is useful in repelling low level hexes and charms, as well as small projectiles. It is this latter use we're going to be taking advantage of."

Tate drew out his own wand. "The second spell we're going to be using is a silly sort of spell that you're unlikely to need in a duel. It is, however, very effective for our activity. The incantation is Pingo, followed by a color, and it produces colored bubbles that leave a washable dye behind where they land. For example..."

He pointed his wand at the chalkboard. "Pingo red!" Small bubbles filled with red dye splattered from his wand, leaving a messy line of splotches across the chalkboard. With another wave of the wand, they were gone.

"If you need to try this spell out, please point your wand at your desk and give it a whirl."