The design of the lab is to provide an easy means for students to understand how to develop a testable hypothesis and follow the scientific method of investigation to determine if there is a relationship between the sugar (or sweetener) concentrations of various solutions and how sweet the solution happens to be? Secondarily, the lab will allow students to address if there is a direct measure for sweetness?
As you know it can be difficult to conceal what we actually think a food tastes like and whether or not we like that food. You know what it’s like, look at the expression of someone's face after biting into a lemon. Even if they enjoy the lemon, there is the immediate puckering effect around the mouth. The same holds true for the beverages we drink, such as sweetened drinks, but there is a problem with explaining the comparison of how sweet something might be to another objectively. That is what we are are going to attempt here by allowing students to explore the use of subjective scales to make objective measures.