The recent discovery of preserved cells and soft tissues in certain dinosaur bones seems incompatible with an age of millions of years, given the expectation that cells and soft tissues should have decayed away after millions of years. However, evidence from radiometric dating shows that dinosaur fossils are indeed millions of years old. Under certain circumstances, cells and soft tissues in bone are protected from complete disintegration. Formation of a mineral concretion around a bone protects biomolecules inside it from hydrolysis by groundwater. Infusion and coating with iron and iron compounds at a critical point in the decay process protects cells within a bone from autolysis. Cross-linking and association with bone mineral surfaces furnish added protection to collagen fibers in a bone. These protective factors can result in soft-tissue preservation that lasts millions of years. It would benefit educators to be aware of these phenomena, in order to better advise students whose acceptance of biological evolution has been challenged by young-Earth creationist arguments that are based on soft tissues in dinosaur fossils.