Discuss the different types of rock (igneous, metamorphic, sedimentary) and the clues students can use to identify an unknown rock (texture, size, lustre, scratch test, etc.). Students are given a rock to observe and answer questions on the activity sheet. After answering the questions students guess which type of rock they have. Wrap up: Confirm which rock each student has, and walk them through the investigation if necessary.
*This activity will require vinegar and rock samples.
