What is the rock cycle? There are three types of rocks — igneous, sedimentary, and metamorphic — that have formed over time in the Earth's different layers. A rock can begin as one type and can change ...

Liam Squires, a fifth grader in Virginia, found a mistake in a book’s diagram of the rock cycle. The publisher said it was “proud” of his discovery. By Amanda Holpuch Liam Squires, like many students, ...