This short classroom activity gets students up out of their seats and making measurements using a different physical device. Students will need to use a spring scale (that measures in Newtons) to find the weight of an object. From there, students will have to use Newton's Second Law to work backwards to find the mass of the object. This should give students the opportunity to see that mass and weight are different, but that they are proportional here on earth.
This would be fun for any middle school or high school physics or physical science classroom.