Science Club Report
Acidity
Is it an acid? Is it an alkali? Or perhaps it’s neutral. The topic of testing acidity using an indicator was explored in our science club lesson last term. Students were given the opportunity to use pipettes and follow through a testing procedure after we shared our thoughts via a PowerPoint. Using a range of everyday materials and household items, students used the indicator to complete a chart, ticking off whether vinegar, for example, was an acid (turned red), alkali (turned a bluish colour) or was neutral (stayed the same colour). Our indicator was made from the liquid of a boiled red cabbage. This can be done at home by an adult, but make sure the windows are open!
Acids and alkalis are two important groups of chemicals. They are dangerous when they are strong but weaker sorts are found in lots of everyday things including foods and drinks. Using a liquid, called an INDICATOR, you can test things to find out whether they are acids or alkalis. Students worked in pairs to conduct a very thorough test on a range of household ingredients such as lemon juice, milk, soap and sauce.
A Thaumatrope
Our most recent session involved students exploring a very popular optical toy from the 19th Century known as a thaumatrope. A thaumatrope can be described as a small disc with a different image on each side and when rapidly spun, the images appear as one.
The purpose of this experiment was to explore how our retina perceives images and what physiologists call “the principle of the persistence of vision”. The thaumatrope fools your eye by switching images so quickly that the images overlap in your eyes, causing them to appear as one. Bringing it back to everyday life, the children were able to relate the basic principles involved in the thaumatrope to how our retina views moving pictures on television and the cinema. The children now understand that movies are made up of long strips of still pictures, each one slightly different from the one before and again our eyes do not view them separately.
Very basic materials were required for this session, yet this didn’t stop the students unlocking their creativity. We had students designing caterpillars on leaves, birds sitting in cages and some children even created a design for their name. The possibilities were endless!
The program Crest is also up and running and we have many enthusiastic Stage 3 scientists who are busily working on their first investigation: the absorbency of paper towel. CREST (CREativity in Science and Technology) is a non-competitive awards program run by CSIRO Education. It provides support for Stage 3 students and teachers to undertake open-ended science and technology investigations. Our Crest students will be involved in leading Science Week activities for our K-2 students during Science Week this term. This year’s Science Week theme is: Our Future Earth.
Mrs Richardson & Mrs Thomas