Create a Skittles Rainbow- dissolving
Place your skittles in a circle around your dish. You could try this in different shapes to see what happens. Once you have completed your circle, add in room temperature water in the middle of the dish. Make sure you add enough to go right to the edge of the Skittles. Wait thirty seconds to see the colours begin to flow. The colour will start dissolving away from the shell, creating a rainbow. Why does this happen? What effect has been created?
Build a Climbing Rainbow- absorption
Cut a strip of paper towel. On a short edge, use felt pens to make a strip of blocks in the colours of the rainbow (You could talk about ROYGBIV here). Let the marker dry. Place the coloured end of the towel in a bowl, and tape the other short end to a vertical surface (e.g. a window). Gently pour water into the bottom of the bowl and watch what happens. Why does the rainbow climb? What has happened to the water? Would this work with a different material?
Colour changing flowers- the job of the stem
Trim your white flowers down and place them in your cup or glass- I would use 4 flowers, one for each cup. Add water to each cup, then put in 10-15 drops of food colouring in the water and stir for 30 seconds. You can use whatever food colouring you have, e.g. red, yellow, blue and green. Observe how the flowers change every couple of hours. What can you see? Why has the flower changed colour? How was the coloured water transported to the flower?