Friday, 8 March 2013

What science do kids need by the end of year 6

Many primary teachers tell me they struggle to understand, and therefore teach, the primary syllabus in science, due to its technical nature. So here's my overview of where we high school teachers want your students to be able to do by the time they head off to high school; the syllabus is in red.

Science Ideas: This is  my point of view as a high school science teacher: I have used the Australian Curriculum, but it is relevant to the current one too. I have used one experiment, dissolving salt in water, to demonstrate what the syllabus is heading the stage 1,2 and 3 students towards.

Australian Curriculum Content

Students question and predict by:
  • with guidance, posing questions to clarify practical problems or inform a scientific investigation (ACSIS231, ACSIS232)
Some chemicals are able to dissolve in water. How can we find out the most amount of salt will dissolve in just one cup of water?
  • predicting what the findings of an investigation might be (ACSIS231, ACSIS232) L
Students will know that salt dissolves in large saucepans of water and that people put about 2 teaspoons of sugar in tea, so they might guess 4 or 5 or 6 teaspoons.
  • applying experience from similar situations in the past to predict what might happen in a new situation CCT
Experiences such as dissolving chemicals in the kitchen. They might also realise that hot water dissolves more than cool ( room temperature) water.
One of the ideas in science is that you can only ask one question  at as time, and you try to make the answer YES or NO.
Say you were asking, Can you keep adding salt to water and make it dissolve?
The answer is if you keep adding salt, eventually no more can dissolve- scientists call this a SATURATED SOLUTION. But that's not important, its just got great illustration and teaches the words solution and saturation!! The main idea, is that you are testing an idea where the answer is yes or no.
Students plan investigations by: 
  • with guidance, planning appropriate investigation methods to test predictions, answer questions or solve problems including surveys, fieldworkresearch and fair tests (ACSIS086, ACSIS103, ACSHE081, ACSHE098)
Planning appropriate investigations means writing an experimental REPORT.
This experiment would look like this;
Hypothesis: That water can only dissolve a limited amount of salt
Aim: To see how much salt you can dissolve in 1 cup water
                          A diagram would be great here.
(Labelled diagrams, should be drawn in proportion, with a ruler and pencil for man made things like beakers, and labelled with a line (rather than an arrow).
look here for more detail Thanks to the makers of this site .
It would be great is the diagram was about 10cmx10cm, as year 7 students tend to draw very small diagrams, or not neat.)
1.  Measure one cup of water and put it in a bigger container( like a bigger plastic cup)
2. Add one teaspoon of salt to the water and stir
3. Observe if all the salt is dissolved
4. Repeat step 2 till no more will dissolve ( you can see it on the bottom of the container
Results:  A table here with the heading Number of teaspoons of salt,  can you see salt ? yes/no
Remember to have a 0 ( zero) as the first " number of teaspoons", which is no.
Conclusion; One cup of water can dissolve 5 ( or whatever) teaspoons of water.
This is exactly the kind of report and test I have done with my year 7's.
LITERACY: Text types: procedure click here for more info!
Note especially,  each step of the method starts with an action word, measure, add, repeat
( so no " well I went and got a teaspoon and we stirred the salt in...")
 Deciding which variable should be changed and measured in fair tests while keeping everything else the same (ACSIS087, ACSIS104) CCT

Here's a memory cue for you : COWS MOO SOFTLY ( Thanks met west) stands for C, M,S
You change one thing ( adding salt), you measure something ( does it dissolve), you keep everything else the same......... this is called DOING A FAIR TEST.
So how could I not do a fair test? Well, I could lie and say I could keep adding salt forever. ( Kids do this all the time in year 7 when boiling water; they often record the  temperature of water boiling past 100 oC which is not possible, or they say it boils at exactly 100 oC, when you expect a number of answers around 100 depending on weather etc)
It would be really great if students came to high school knowing they had to record the actual truth in science. There are some great examples in science when people "knew" something was true so didn't make observations or do the experiment.  For instance, everyone knew heavy objects fell faster than light object till Galileo did the experiment from the leaning tower of Pisa.
Another way to cheat would be to introduce another variable. Eg if you started heating the water half way through the experiment, switched to another chemical like sugar , added more water or add another chemical like metho you have not done a fair test. Heating will definitely make a difference, and in science we MUST only change on variable.  We often do see if heating allows more salt to dissolve in year 7 science; in that case the independent varible is temperature and dependent in amount of salt that dissolves.
  • collaboratively and individually selecting suitable methods for gathering data and information first-hand and from reliable secondary sources LPSCWE
This is really about measuring when doing first hand experiments. Now, we have heaps of great equipment for measuring in high school , but you are really helping your students if you use teaspoons and cups to measure things DELIBERATELY when doing science. Under quality teaching framework (QTF), its connected knowledge about measuring in the home, plus it gives us a great launching pad in year 7 to use the specialist gear.
Students conduct investigations by:
  • working individually and collaboratively in conducting a range of appropriate investigation methods, including fair tests, to answer questions or solve problems PSCWE
  • using suitable equipment and materials, checking observations and measurements by repeating them where appropriate
This means doing the experiment more than once, to make sure it works.
  • using equipment and materials safely, identifying potential risks (ACSIS088, ACSIS105) PSC
Any action that protect the person, as long as its stated eg
The salt might splash in your eyes, where goggles is what we would say in high school. Glass container might break and cut you so  use a plastic container
  • accurately observing, measuring and recording data, using digital technologies as appropriate (ACSIS087, ACSIS104) ICTL
However, counting accurately and making sure your observations are right also counts. Accurate measurement would mean using a proper kitchen measuring spoon and levelling off with a butter knife. Accurate observing means using a clear container and putting over black paper to make sure the salt is dissolved properly or not. Accurate recording means using a table, not using subjective descriptions.
Use a ruler,  thermometer, scales etc where appropriate.
Note the small the unit ( mm versus cm) the more accurate.
I don't know what sort of digital technology a primary school is expected to have handy.... maybe a camera ? ( Honestly, we HS teachers have special gear for this.)Perhaps you can use kitchen scales to measure the weight in grams, instead of using the teaspoons? )
  • using formal units and abbreviations for measuring and recording data N 
This means g for grams. Also, I try to get students to write the units (g) next to the approprate title on the table, rather than writing grams throughout the table eg
Weight (g)
Can you see salt ( yes / no)
  • suggesting improvements to the methods used to investigate a question or solve a problem (ACSIS091, ACSIS108) CCT
Improvements such as weighing in grams, seeing if warm water or cold water dissolves different amounts of salt, testing other soluble things eg sugar, tartaric acid. ( Be careful because a lot of things like cornflour, flour , dirt etc don't actually dissolve)
Students process and analyse data and information by:
  • constructing and using a range of representations, including tables, graphs ** (column, picture, line and divided bar graphs and labelled diagrams NL
  • there's no graph for other experiment but you could take photos! A labelled diagram would be great too!
NUMERACY: Drawing a scientific table

By high school we are trying to make sure both variables are  mentioned in the title:

Title: How many teaspoons of salt dissolve in one cup of water.

Number of teaspoons
Is the salt dissolved?( yes / no)

No lines except how I've drawn it, use a ruler, and notice we start at zero!

Also the first column is for what you decided, (so you could go 0,2,4,6,8 teaspoons if you want, or any other measure). If you're a scientist, you call this the INDEPENDENT VARIABLE ie I decided to add 1 teaspoon of salt, so this is the I for Independent variable. But you don't need to use that fancy language- leave that to us in high school!!

Then once you've got the table written down, you do the experiment. The results you write down DEPENDS on the experiment. (So this is the DEPENDENT variable for those paying attention). "What do you record?" Well it depends on what happens.
Using numerical techniques to analyse data and information, including calculating the means and percentages of small sets of data N
  • If you had a number of groups doing the experiment, then take average ; numeracy again. This makes the experiment more reliable . Repeating ( either one after the other or multiples times at once) is for reliability.
  • ** graphing: a line graph is for continuous data, for discrete data use a column graph. Our experiment can't really be graphed. ( or there's no point because it would be one column )
    I'll do a more complex experiment later to show this.
  • drawing conclusions and providing explanations based on data and information gathered first-hand or from secondary sources CCT
  • The conclusion should have both variables mentioned; 5 teaspoons of salt dissolved in a cup of water.
  • comparing gathered data with predictions, and using as evidence in developing explanations of events and phenomena (ACSIS218, ACSIS221, ACSHE081, ACSHE098) CCT
  • Get students to guess how many teaspoons would dissolve. this is the prediction. perhaps you can take a vote and the most popular number becomes your prediction; 7 teaspoons of salt will dissolve in a cup of water.
  • reflecting on their gathered evidence in relation to: CCT
  • State whether the prediction was a good one.

  • the process used to gather, process and analyse their data and information
  • How can we improve the experiment ? There's always ways. In this case you could measure in grams, or do more than one house hold chemical. Again, i will deal with this later.
  • their own prior knowledge as well as accepted scientific explanations
Brainstorm what students know about household chemicals that dissolve.
  • their own and others' conclusions
Students communicate by:

  • constructing and using a range of representations, including tables and graphs, to represent and describe observations, patterns or relationships in data including using digital technologies as appropriate (ACSIS090, ACSIS107) NICTLCCT
  • publish their report with photos- assessment task including literacy and numeracy
  • do a speech about their experiment.
  • suggest another experiment that could be performed using the same format
  • using a variety of ways to honestly and accurately communicate ideas, explanations and processes, including multi-modal texts, labelled diagrams, as well as written and oral factual texts as appropriate (ACSIS093, ACSIS110) LEUNICT

1 comment:

  1. Hi Marianne, Yay for you!! This is something I will show Steven - he started Year 7 this year and I know he will find this very useful!