Behold the beauty of gems that change colours! Mood rings are said to change colour depending on the mood of the person who is wearing them. Students will be asked to investigate this claim by seeing if they can change the colour of a mood ring (without having to change their mood!) Students will pose their own question and answer it by planning and conducting their own experiment. Students choose how they will collect and analyse data, and are asked to evaluate the reliability of their results.
Water beads, also known as water crystal gel, are composed of a polymer that can absorb large amounts of water. A polymer is a very long molecule, and the polymers in water beads can typically absorb up to 200 times their weight in water. Water beads are usually made from a polyacrylamide such as sodium polyacrylate, which is commonly known as a superabsorbent polymer or slush powder in dry form.
Science in a Bag
One way of knowing that a chemical change has occurred is by observing that the properties of the product are different from those of the reactants. There are four simple ways that students can recognise a chemical reaction has occurred. In this experiment, two mystery white powders and a blue liquid are added to a bag and the bag is sealed. The mixture changes from blue to red, one powder cools the liquid as it dissolves, the other powder warms the liquid, bubbles are produced and the bag pressurizes.
Stomata on Leaves
Concentrated on the lower leaf surfaces are tiny openings called stomata that allow gases to pass into and out of the leaves. The stomata are surrounded by guard cells that collapse and swell to close and open the stomata, depending on the plant’s needs. Students can tear a leaf with a waxy cuticle (jade, calla lily, or philodendron, for example) to expose the lower epidermis. Using a microscope, they can count the number of stomata that are open and closed.
Science in Your Pocket
Who has ever imagined that we could have carried a compact mobile laboratory in our pocket! This is simply true today at a click of a finger. Our smart phone can do much more than we can imagine. In addition to being a tool for communication, a camera, a torch, a translator, a GPS, an alarm, a stopwatch, a diary and much more, it can also be used to do very sophisticated measurements. In this experiment, students will use an application on their smart phone to measure the change in intensity of light with change in distance from a light source.
Freshwater Indicator Species
In this investigation, students will play the role of a biologist in a water pollution consultancy business. It is their job to examine samples and make determinations about water quality. Students will use their scientific skills to make predictions, identify and classify organisms, record and analyse data, and present and justify their findings. This investigation can be extended to an excursion, where students collect their own samples, or adapted as a classroom activity by having samples prepared beforehand.
Energy in Food
This experiment is an excellent demonstration of how energy can be transferred from one system to another (food to water) and how it is transformed from one form to another (chemical potential energy to heat energy). Students will have the chance to learn why controlling variables is important and how to design a reliable experiment. They will study the energy released when different types of food are burned and will confirm which food contains the most energy.
This investigation is for the adrenaline junkies out there! Bungee jumping can be both exciting and terrifying, but it cannot be conducted in an ad-hoc way. There is a lot of planning and testing in place for jumpers to stay safe. This engaging topic forms the basis of this open-inquiry investigation. Students will be asked to use experimentation to make well-informed predictions. Students will be engaged further when able to explore the interesting
physics that underpin a bungee jump.
In this experiment, students will practise their laboratory skills and apply scientific knowledge in order to evaluate whether they should accept certain claims. It is well known that some fruits such as pineapple will prevent Jell-O or other gelatine products from gelling. Students will be asked to design an experiment to test this claim. They will also explain their findings using scientific theory. While the teacher will be checking their design and procedure, students will have the freedom to choose the best way to conduct the experiment. Hence, they will experience the power of scientific research in assessing claims and will use their critical thinking to evaluate their results and make conclusions.