Some chemical reactions give out heat energy, others need extra to work. Observe changes in temperature that happen with experiments and learn about exothermic and endothermic reactions.
All numbers have an even number of factors, with the exception of square numbers. You will be able to show this visually in the following experiment.
A very simple and colourful experiment using candy to explore basic paper chromatography.
A demonstration which shows just how important the interaction between the human mind and a computer is by illustrating the Stroop Effect.