Biochemists not babies!
A simple recommendation here:
carbohydrates, give them solid glucose, get the students to explore the properties, its crystalline, sweet, it dissolves.
Dissolve a couple of spatula worth of glucose in a boiling tube and add enough Benedict's solution to turn it blue. Into the water bath........record the colour change.
Don't start with prepared solutions, students don't know this from water. Give them the solid stuff.
Repeat with start, demonstrate the lack of solubility...you see if you make up a starch suspension this point is missed.
Start them on solids
