This document discusses methods for determining the relative age of rocks and fossils, including using the principle of superposition, where older rock layers are found below younger ones, and examining index fossils, which are fossils that lived during a short period of time that can help date the rock layer. It also mentions radiometric dating as a way to determine the absolute age of rocks and fossils by measuring the decay of radioactive isotopes. The document provides questions for students to think about the geologic column and which layers and fossils are oldest versus youngest.