Use this activity after teaching students about the metric system. It allows them to use scientific measuring tools in the classroom and practicing conversions. You will need meter stick, electronic balance and graduated cylinders for students. You will also need objects for students to measure. Use the lab table in the classroom for length, for volume choose a variety of containers that students can fill with water and then measure using a graduated cylinder. For mass, choose something small around the classroom - an eraser, a pencil, a beaker, etc.