What might this be?

Definition of catapult…

1. An ancient military device for hurling missiles.

2. A catapult is a ballistic device used to launch a projectile a great distance without the aid of explosive devices—particularly various types of ancient and medieval siege engines.[

International STEM Challenge

Crazy Catapults

All Year 7 students are going to be building catapults from lolly

sticks...

How might we decide whose

catapult is best?

See how other students around the world have tackled this challenge…

• https://www.youtube.com/watch?v=PMvfPqdX8JE

Assembly of catapult

1. Watch the video and be ready to feedback on:-how good you think the method for making the catapult is-why you think this -whether you think this method could be improved

https://www.youtube.com/watch?v=3w8kR8tgZr8

So, let’s give it a try and put the method to the test…

In your teams decide how you are going to involve everyone

1.Get all of your equipment ready2.Start making your first triangle. Remember, follow the instructions.3.You need to make 3 of the triangles before you can construct your ‘geodesic triangle’.4.Now you need to build the arm.5.Next you need to construct the cup.

How well are you working as a team?

Can you calculate the maximum possible score?Use the Scoring for Crazy Catapult sheet to calculate the maximum possible points you can score.

The first calculation has been completed for you.

Remember, the further away the more you can score

How did you do?........

Shooting position 1 maximum score

Shooting position 2 maximum score

Shooting position 3 maximum score

= 45pts (e.g. 15+10+5+5+5+5)

= 55pts (e.g. 15+10+10+10+5+5)

= 65pts (e.g. 15+15+10+10+10+5)

Now let’s test our catapults…

How do we know what kind of graph should we draw?

Are the independent and dependent variables categoric or continuous?

Read the definitions and decide…..

Categoric variable:These are variables which have values in the form of words instead of numbers (e.g. for the independent variable ‘type of plant’ this would be categoric as the values would be words ‘daisy’, ‘dandelion’ etc).Continuous Variable These are variables which have values in the form of numbers (which you can obtain either by measuring or counting).

Key points for Graph DrawingUse a sharp Pencil and rulerInclude a descriptive title (that makes it clear what the independent and dependent variables are in your investigation)Dependent variable on the Y axisIndependent variable on the X axisUse an appropriate scale (must be ‘linear’)Label axis with variable name and unitsMake use of as much of the graph paper as possiblePlot all points neatly with a small crossCircle any possible anomaliesDraw a line of best fit with a ruler for a straight line or draw free-hand for a curved line (don’t join up as in a ‘dot to dot’)

How to draw a bar graph

Num

ber o

f car

s

DV always on the y axis

IV always on the x axisEvenly spaced scales

Bars the same width and an even gap

between each bar

Everything drawn with a ruler

Axis labels and units

Axis labels and units

Graph fills the page

Swap and PEER ASSESS

• Tick if achieved, cross if not. Write something specific your peer has done well (WWW) and explain anything that they need to do to improve their graph EVEN if they got 9 ticks (EBI)

Bar Charts

Pencil and ruler used

Detailed title (includes IV and DV)

DV on Y axis

IV on X axis

Labelled axes (variable+ unit)

Suitable scale

Graph fills most of page

Key for bars

Bars equal widths

Equal sized gap between bars

Who Won In Your Class? Why do you think this happened?

Who Will Win in Year 7?