Pour some coloured bubble mix in a tray/cup. A cup will need less mix, but a tray is more stable.
Blow bubbles in the paint/bubble mix with the straw.
Lay the paper over to make a bubble print.
Repeat in another colour paint/bubble mix.
Prompt students with questions to help them observe the bubbles closely if necessary:
What shapes are the bubbles on their own and when next to each other?
What happens to the shapes if a bubble is popped?
Science of bubbles can include:
the shapes of the bubbles (separated and attached) and how they fall into the most stable configuration;
the structure of bubbles - the skin is a layer of water molecules between two layers of detergent molecules, which encloses a pocket of air molecules.