These unique scales have transparent cases that allow you to see the working mechanisms. The kitchen scale is very robust, and has an all metric dial. Marked in 10g increments.
Scales are often used in both maths and science classes. Students have to use scaled instruments to measure and compare masses.
 
Students can compare objects of the same size while seeing if they are the same in weight. Or find two objects that are the same weight but a different volume. In science, kitchen scales are used to accurately measure the desiredamount of ingredient for chemistry activities.