This is an Excel table designed for students to practice finding mass using a triple beam balance. First they bring in cans or boxes of food from home (this can be done philanthropically--donated later to a food bank). Next, each student masses the cans and boxes and writes the value on their data table. Then they write the mass from the food label. Next, students compare their measurements with those on the label. Their measurements should always be less than the label. This fosters the discussion as to why this occurs. Students may think it is because they measured incorrectly, but it is actually because they are not including the mass of the can on the label--only the food itself. Students can subtract to get the actual container mass. You may also discuss careers in quality control...The activity basically gives students practice in finding mass.