The Moving Picture Card

I grabbed the glossy corner of a thick rectangular card resting on the coffee table. The picture on top showed a bright green cartoon frog perched on a lily pad. But the second I lifted the card to inspect the ribbed plastic surface, the frog suddenly leaped straight up with both legs kicking out! I froze, blinked, and tilted the card back down. Plop—it was sitting peacefully on the leaf again. I spent the next few minutes rocking the card up and down like a seesaw, making that little frog jump, land, and jump all over again.