I’ve written extensively about rewriting KS3 here. In short, the idea is to specify a curriculum as a series of questions which need to be answered. The advantages of this method are:

  • No ambiguity about what is to be taught
  • Consistency of language
  • Consistency of assessment
  • Appropriate sequencing of knowledge requires teachers to really think about their subject
  • Powerful tool for student long term memory
  • Powerful tool for sequencing in the classroom and breaking material into small pieces

I am currently writing a scheme for a How Science Works unit. In the past, this has tended to be taught in kind of a haphazard way with a lot of unstructured progression through graphing, some practical work, endless mention of fair test, constant confusion of students regarding variables and, of course, a do-it-yourself investigation.

I wanted to clean things up a bit and bring it more into line with the overarching philosophy. I’ve written Core Questions for the topic and have drawn heavily on the ASE’s Mathematics in Science document. It’s been incredibly difficult but what I have so far is below.

I’ve tried to thread two canonical examples throughout the unit. You cannot talk about HSW without specific examples so I have limited it to two which are based on concepts students have already learned to a high level and can be illustrative examples throughout the unit (along with others where necessary too, but these will be the main ones). Throughout, I have obviously had to (over)simplify and be pretty ruthless with ambiguity. This is for students in KS3 and just has to cover the basics in a rigorous but straightforward way.

Anyway, I would really love people’s opinions on the way I have specifically worded and sequenced the questions and any errors or omissions. You can either comment in the comments here, on twitter or on this live google doc that some of my colleagues are already commenting on and elaborates on some of my thinking too (especially on language surrounding variables). Thanks in advance!


Theories and evidence What is a scientific theory? An idea used to explain events
What is the theory of conservation of mass? That atoms cannot be created or destroyed in a chemical reaction, just rearranged
What does the theory of conservation of mass explain? How masses of reactants and products change in a chemical reaction
What is the theory of interdependence? That animals and a plant in a food web depend on each other
What does the theory of interdependence explain? How the populations of organisms in a food web can change
How are theories proved or disproved? By collecting evidence
What is evidence? Information that can be used to prove or disprove a theory
How is evidence generated? Through a scientific experiment
Types of data What is experimental data? The information collected from an experiment
In what three ways can data be generated in an experiment? Through measurement, observation or counting
What is a measurement? The result of an experiment that can be measured with scientific equipment
Given three examples of measurements Mass, distance, time, force, wavelength, temperature
What is an observation? Something that can be seen in an experiment
Give three examples of observations Colour, giving off light (luminescence), giving off gas, movement, change in state
What are the three types of data? Continuous, categorical and discrete
What is continuous data? Numerical (number) data where the number can be any size
How is continuous data generated? Through a measurement
Why is the mass of a substance continuous data? Because the mass can be any number
What is categorical data? Data which has no numbers but can be put into categories (groups)
How is categorical data generated? Through observation
Why is eye colour categorical data? Because there are no numbers but the different colours can be categorised e.g. blue, brown
What is discrete data? Data with numbers, but only certain numbers are allowed
How is discrete data generated? By counting
Why is the number of animals in a certain area discrete data? Because it will be a number but only whole numbers are allowed (you cannot have half an animal)
Variables What is a variable? Something that changes in an experiment
What are the three types of variable? Independent, dependent and controlled
What is an independent variable? A variable that could be changed by the scientist
What is the dependent variable? The variable that is observed, measured or counted by the scientist
What is a controlled variable? A variable that is kept the same throughout the experiment.
What is a fair test? An experiment where all possible independent variables are controlled other than one
Why is it important that tests are fair? So that you know which variable was having an effect
Give three variables that could affect the mass of a product from a reaction Mass of reactants, time allowed for reaction to take place, temperature at which reaction takes place
Give three variables that could affect the number of organisms there are in a certain area Human activities, environment, disease
Features of experiments What is a scientific prediction? A prediction about how the independent variable will affect the dependent variable
What is reliability? How likely your results are to be repeated
How can you increase the reliability of your experiment? By repeating it and taking a mean
Displaying results What is a table of results? A table showing experimental data
What are the key features of a table of results? Drawn in pencil with a ruler, units in brackets
What are charts and graphs? Ways to present data
What are the most common types of chart and graph? Line graph and bar chart
What kinds of chart and graph are most common? Bar charts and line graphs
What data is best presented in a bar chart? Categorical or discrete
What data is best presented in a line graph? Continuous or discrete
What are the key features of charts and graphs? All drawn in pencil, on graph paper, title, labelled axes, units in brackets, appropriate scale, uses half the page
Which axis does each variable go on? Independent on the x, dependent on the y
What is a scale? How the boxes on the graph paper relates to the values
How should scales be drawn? Each large box represents 1,2 or 5 as a multiple of 10
What is a line of best fit? A line that best fits the data
What are the two types of line of best fit? Straight lines and curves
Interpreting results What can the line show you? A scientific relationship
What is a scientific relationship? How the independent variable affects the dependent variable
How can relationships be described? As x increases/decreases, y increases/decreases
What is a conclusion? A statement that says whether your prediction was correct