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Projects on this page are arranged by subject category, and not by age or ability level as they are only meant to be suggestions for research and should be tailored to your own particular needs. The page is still under construction, so is still full of gaps at present, but it should start filling up soon!
Stimulating Woodlice
This short investigation uses woodlice, or probably any other "bug" you can get your hands on, and it looks at how they react to what's going on around them. We will be asking the question "what does my bug do if its light/dark/wet/dry/other ?" As an example, let's consider the response to light and dark.
Apparatus
Instructions
Draw a line down the middle of the dish. Now place a known number woodlice on the dish and allow them to move about a bit so they are randomly distributed. Count how many woodlice are on each side of the line, then place the piece of black card over half to the dish to make that half dark. At intervals of 30 seconds count how many are on the light side. Continue for a few minutes.
Does the number of woodlice on the light side go up or down? What happens if you start them off all on the light side, or all on the dark side? Why do you think they behave as they do?
Further Investigations
Wet/Dry - use cotton wool on the dish and dampen half of it
Both together - arrange the dish into quarters (light and dry; dark and dry; light and damp; dark and damp)
Some other stimuli - Can you think of anything else they might react to
Chromatography
Chromatography is often used to separate complex mixtures of compounds, but one of its first uses was to separate the chemicals that make up chlorophyll - the green colour in leaves. This can be done easily, and you could investigate different leaves to see if they contain the same chemicals in the same ratios. That is, is there more of that colour in this leaf than there is that one? Leaves that are obviously different colours lend themselves to this particularly.
Apparatus
Instructions
Cut the blotting paper into small squares, or circles, about 3" (7cm) across. Take the leaves and crush them with the mortar and pestle, adding a little water to make a paste, add more water until it is quite runny. Now take some of the liquid in the dropping pipette. If you are using a biro to 'suck up' the liquid I recommend practising with normal water first to get the hang of it. Now put a drop of liquid in the middle of the blotting paper. (The amount required may take a bit of practice, so try again if it doesn't give great results first time.) The liquid should spread towards the edges of the paper, and as it does so it will separate out into several different colours giving a attractive pattern on the paper.
Further Investigations
As mentioned above, this project could be extended by investigating the leaves of many different plants. Are the colours in garden grass the same as those in the leaves of oak trees.
You could be more scientific in analysing the colours by being exact over how much water and leaf you add.
If you're feeling like a bit of mental exercise and have done some chemistry, think why some chemicals travel faster, and therefore further, than others.
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