You might describe someone particularly talkative or gossipy by saying that their tongue wags at both ends. A more elaborate version is Your tongue wags at both ends and is tied in the middle. Another variant: Your tongue is hinged in the middle...
In the United States, playing hooky from school is often called skipping school. Lots of other terms for truancy throughout the English-speaking world. In South Africa and India, it’s bunking. In England, you might describe that activity as wagging...
wig-wag n. a rapidly alternating or strobing warning light. Also attributive. Editorial Note: Often plural, since the lights are rarely used singly. Semaphore flags have long been called “wig-wags” in the Navy, Marines, and other...