In sixth grade science, students are investigating how we know if something is living. To do this, sixth grade scientists set up an experiment to test whether a collection of mystery materials are living or nonliving. Groups of students prepared five vials, each containing a mystery material along with one type of mystery liquid. The type of liquid used varied between the groups, but all student groups had the same type and amount of mystery materials in each of the vials. Over the course of several classes, students will make and record their observations in the form of sketches and precise notes. By the end of the experiment, students will discover which of the materials are living as well as how the living things responded to each of the three mystery liquids. This experiment will serve as a springboard for further discussions on the characteristics of all living things, the understanding of which will evolve over the next several months.