Nadia and the Vanishing Footprints

Every morning that week, a trail of small footprints crossed the snowy schoolyard. Nadia spotted them from the gate before the bell. By noon, they had always vanished.

At recess, her classmates shared their theories. A lost penguin. A sneaky cat. A tiny snow robot that walked at night and switched itself off at lunchtime.

Nadia pushed up her round glasses and wrote every theory in her notebook, even the robot. Then she said, “A snow robot would be amazing. But a detective needs clues, not guesses.”

After school, Nadia ran to Grandpa Teo’s house. For thirty years he had looked after the weather station on the hill, and he still read his thermometer every morning.

Grandpa Teo listened to the whole mystery. Then he tapped the thermometer and said, “Footprints don’t just vanish, Nadia. Something takes them away. Tomorrow at sunrise, bring your ruler.”