This activity presents a plan for varying the amount of glycerin while keeping the amount of water and dishwashing liquid the same. From the basic bubble mixture 8 bubble solutions have been made. Here is one suggestion you can do lots of others, eg use different brands of detergent, put gelatine, golden syrup, sugar… in some, have some fresh and some old….
Show the students the glycerin. Ask the students if they have any expectations about the experiments. Which mixture do they think will make the largest bubbles? Which mixture do they think will make the longest lived bubbles?
Divide the students into 8 groups, with at least two children in each group. One student will blow the bubbles, the other will measure how big they are. For each of the 8 solutions, get a student to use a drinking straw to blow the largest bubble possible, while the other student measures the diameter of the bubble using a ruler or a marked sheet of paper. The diameter is from the tip of the straw to the furthest part of the bubble. A third student can write the results into the notebook. Repeat this at least 10 times and record the overall largest bubble and the average size of the bubble.