Introduction: Teach Investigative Science With a Simple Glider
I've been using this glider to teach general science skills for some time, and so many colleagues have reacted positively to it, I thought I'd share it with the wider world.
Don't worry; if you only want to learn how to make the glider, I'll make the educational parts obvious so that you can skip over them.
Step 1: Making the Basic Glider
I may be boasting, but this glider is one of the simplest, and most elegant gliders I know. I started out using more complex gliders in lessons, but I found I was spending more time teaching how to make gliders than I was working towards the lesson objectives. Over time, I simplified the glider to the point where learners refuse to believe it will fly, until they see it in action.
Start with a rectangle of paper. For convenience and scale, I typically start with a sheet of A6 paper - a normal piece of A4, cut into four parts:
- Fold the long edge of the paper over about 3-5mm, about five or six times.
- With the folded edge faced down, drag the paper over the edge of a desk to make it curve.
That's it, you're finished. If you've made it right, you should have a piece of paper, curved like a gentle smile, with a folded edge sitting on top of the smile.
If you find you cannot make a curved glider fly straight, you can, instead, switch to a single crease down the centre of the glider (see the last photo). This option also makes step 7 a bit easier.
Step 2: Flying the Glider
This glider has a number of benefits in a classroom situation; being slow and square, it does not present a hazard to eyes, and it cannot be thrown, so it does not end up on high window ledges, or behind tall cupboards.
Because it cannot be thrown, flights are normally restricted to distances that fit well within the classroom, no matter how strong the thrower. Well-muscled thugs can be beaten by the smallest member of the class.
To launch the glider, hold it between finger and thumb, with the folded edge facing away from your hand.
Hold it high, point it down slightly, and give it a gentle push as you let go.
If the glider curves in flight, a gentle twist of the wings can fix it. If it curves left, give a small upwards-curl to the back-left corner. If it curves right, give a small upwards-curl to the back-right corner.
If you're not interested in the gliders as an educational tool, you can stop reading now, but if you're interested in modifications, skip ahead to step 7.
Step 3: The First Science Bit: Variables
A large part of UK science education in high schools ("K12" in the US) is based on "investigations" (sometimes called Sc1 or Science 1, thanks to the way the government ordered the National Curriculum). These gliders are particularly suited to investigations at Key Stage 3 (ages 11-14).
One of the areas of investigations that many learners have is the concept of "variables" (things that could be changed in the experiment).
First, they have to recognise that not all variables are relevant to the experiment. The colour of the paper will not affect the flight, but the thickness or roughness of it probably will.
Second, they have to sort the relevant variables into one of three groups:
- Control variables. These are all the variables that might affect our results, but we are going to keep the same throughout the experiment. This is part of ensuring a fair test.
- Independent variable. This is what we deliberately choose to change during the experiment. Come the final analysis of our results, the independent variable would be plotted along the horizontal axis of a graph.
- Dependent variable. This is what we measure during the experiment, our results (its value depends on the independent variable). On a graph, the dependent variable would be plotted on the vertical axis.
Be aware that independent variables are sometimes referred to as "input variables" and the dependent as "output variables". If you are a UK student reading this, please avoid these terms, as examiners now insist on the the terms independent and dependent.
In your lesson, get your class to list as many possible variables about the gliders as they can, then select a pair of variables to focus on.
If you need to guide them, the "easiest" independent variables to work with are;
- Height the glider is launched from.
- Angle the glider is launched at.
- Wing-span of the glider.
- Length (front to back) of the glider.
For the last two, it is a good idea to give the learners pieces of graph paper to make the gliders, then they can trim parts off along regularly-spaced lines.
The dependent variable is almost always "range of flight", but I have also known children measure the duration of the flight, or to count the number of times the glider dips and semi-stalls in flight. They may also choose to measure the glider's speed, which will involve measuring both the distance it glides and the time taken to travel.
Step 4: The Second Science Bit: a Hypothesis
By the end of the previous step, the learners should have reduced everything to a single question, along the lines of How does the value of X affect the value of Y?
- How does the launch height affect the distance a glider flies?
- How does the wingspan of a glider affect the number of times it stalls in flight?
- How does the angle a glider is launched from affect the speed it flies?
They should also have an idea of what the answer will be, based on a mixture of previous experience, existing science knowledge, and possibly on preliminary experiments (fiddling with gliders) and research.
This idea is referred to as their hypothesis, and learners need not worry about getting the answer "right", just about making a decent case for their idea.
It is a good habit to structure the hypothesis as a single sentence along the lines of; I think that X will happen because Y. Higher-level students can go on to make supporting statements based on their previous work or research, but everybody should produce at least that first sentence.
Step 5: The Third Science Bit: Doing the Experiment
This is the easy part.
The groups find themselves some space, and fly their gliders, measuring how far they fly.
It's up to you as their teacher to guide or monitor their measurements, depending on their ability and your specific objectives for the lesson. It could be rulers laid along the floor, a tape measure or whatever you like.
What is important is that they mention the method they used when they write up their report, and that they record several measurements for each value of the independent variable. That is, they repeat for reliability: they should launch the glider at least three times for each value of the independent variable, and record every measurement.
Step 6: The Fourth Science Bit: Analysing the Data
Again, the analysis performed is determined by the ability of the learners and your own objectives as a teacher.
Typically, though, they will need to calculate the mean of each set of measurements, plot those values onto a line graph (probably with a line of best fit), then draw a conclusion from the data.
A good conclusion will have three parts:
- A simple statement describing any trends in the experimental data.
- A reference back to their hypothesis, stating whether the results support the hypothesis or not.
- A reference to the actual data, explaining why they made the statement about the hypothesis.
For instance, they might say;
We found that the greater the wingspan, the further the glider flew. This agrees with our hypothesis, because the 15cm wide glider flew an average of 4.6m, and every time we trimmed a centimetre off the wings, the distance flown also decreased, until the 5cm glider only flew an average of 0.8m
(Note: these numbers are plucked out of thin air)
Higher level students should also be encouraged to say something about the quality of their data. Specifically, whether there were any anomalies, and how they dealt with them (such as ignoring unusually short flights and re-trying them).
Step 7: The Bit That Overlaps Into Technology Lessons.
As well as science, these gliders can be used to help younger students get to grips with the basics of designing to a brief, avoiding stereotypes, and considering manufacturing processes in the design stage.
To many younger students, "design" means "draw a picture of your favourite cartoon character on it, or colour it to match your team's home strip".
You can use these gliders to help them get over this:
Show them the basic glider, and explain that a printing company wants to sell them to different companies them as advertising freebies. It is the the children's task to redesign the glider in as many different ways as possible, to advertise as many different kinds of company as possible.
If you then chop off the back corners, to make a triangle, and demonstrate that the glider still flies well, you can also encourage them to change the shape of the glider.
Let them play with their ideas, trying out different shapes and evaluating them for flyability, ease of manufacture (how fiddly was it to cut out?), and what kind of company the shape might be sold to.
I have seen the basic glider modified to resemble traditional aeroplanes, butterflies, bats, sandwiches (the triangle) and even a doughnut.
Because symmetry is important, it is easier to modify the glider outline by folding in half and cutting both wings at once. This means it is better to use the "centre crease" option when making the actual glider.