Jenna quickly finished her drawing. Wait--I'm forgetting something, she thought. She remembered the spell she had learned in Charms one day. She did a weird wand movement, whispered, "Alacer!" and the picture began to move. She stuffed the drawing in her bag and paid attention to what was going on.

Jenna raised her hand. "It's an abacus, isn't it?" she asked. "And you use them to make calculations, right?"