ACARA v9 CONTENT DESCRIPTION “consider how people use scientific explanations to meet a need or solve a problem”
Builds on noticing how the world works. Now we look at why people bother to find those things out. When you know a science idea, like heat melting ice, you can use it to meet a need or fix a problem in everyday life.
A science idea can solve a real problem
Science is not just for the classroom. Every day people use what they have learned about the world to make life better. Someone found out that warm air melts ice. That one idea leads to a clever solution: to keep ice cold, you must keep the warm air away from it. From that thought comes the cool box, or esky, that holds your food cold on a hot day at the beach.
From a science idea to a useful solution
Add each new idea in turn and watch how knowing how the world works leads people to build something that meets a need.
New evidence (1 of 4)
People notice that ice melts quickly when the air around it is warm, and stays frozen longer when the air is cold.
Accepted model: The need: keep food and drinks cold on a hot day, even with no fridge nearby.
Add the next piece of evidence and watch whether the accepted model holds or has to change.
Choosing between solutions
Often there is more than one way to solve a problem, and each way has good points and not so good points. Imagine you need to carry cold drinks to a picnic. You could take a big cool box, a small one, or just a wet cloth wrapped around the bottles. Each choice keeps the drinks cool in its own way, but each also gives up something. People weigh these trade-offs and pick the solution that fits the need best.
Pick a way to keep the picnic drinks cold
You know that thick walls keep heat out and that wet things lose heat as they dry. Choose a solution and see what you gain and what you give up.
You are walking to a picnic and you want your drinks to stay cold. You know warm air melts ice and that thick foam slows heat down. Which solution will you take?
Choose a response to see what is gained and what is given up.
Which choices really use a science idea?
A farmer wants the carrots to grow big and strong. The farmer knows a science idea: plants need light to make their food and grow. Some of the choices below use that idea to solve the problem, and some are just about how things look or feel. Sort each one into whether it really uses the science explanation that plants need light.
Does the choice use the science idea that plants need light?
The science idea: plants need light to grow well. Decide which choices use that idea to help the carrots grow.
Claim: Knowing that plants need light helps the farmer grow strong carrots.
The farmer plants the carrots in an open field that gets sun all day, not in the shadow of the barn.
The farmer trims the tall weeds that were blocking the sunlight from reaching the young carrots.
The farmer paints the garden fence a bright, cheerful red.
The farmer spaces the rows apart so no plant shades the one beside it from the light.
The farmer chooses a tractor because its colour matches the barn.
Decide whether each statement is evidence for the claim, or not.
Why this matters
The cool box, the sunny field and the warm coat all started as a science idea about how the world works. People learn how heat, light and water behave, and then they use those explanations to meet a need or solve a problem. Once you see this, you notice science all around you, quietly making everyday life work.
Quick self-check
1. People found out that warm air melts ice. How did that science idea help solve a problem?
2. A farmer knows that plants need light to grow well. What problem does that idea help solve?
3. Which of these is using a science explanation to meet a need?
4. When people pick a solution to a problem, why is there often more than one good choice?