Physics First – an Argument on Sequencing
“Right class, please turn to page 5 of your exercise books, we are going to be learning about Cells today!”
For years textbooks revision guides and specifications have started with Cells. Why? Well Biology comes first alphabetically so of course that makes sense. As for Cells, we need to know about the basic building blocks of Biology, right?
Well yes… but not just yet…
Interestingly the majority of eduTwitter may disagree with me. A very non-scientific poll revealed around half of teachers start with Cells in Year 7, around one in five schools start with particles.
Those teachers who opted for “something else” mainly commented on either:
- A rotation system to ease the pressures on equipment – there were some interesting combinations of subjects used on rotations but most included Cells in some form
- An introduction to science topic (they hadn’t read the question! Tut tut…)
Last summer I wrote extensively about the approach of my department to sequencing at KS3. (You can read the full blog here.) In my first article for Chat Physics I am aiming to explore the importance of Physics in developing a strong and secure schema at KS3.
Cells Can Wait!
At the time of writing, Gateacre School Year 7 students had only just covered Cells. (The COVID-19 shutdown of schools was March 20th 2020). But why?
Cognitive science tells us that students learn by committing knowledge into their long-term memory, which can then be secured via retrieval practice. This learning forms an interconnected web of knowledge that we call a schema.
Image taken from Tom Sherrington’s Rosenshine’s Principles in Action
Schema can be strengthened further by ensuring that new learning builds on existing knowledge. This is where the skill of the teacher comes in as we try to ascertain what our pupils already know and understand by assessing prior knowledge through skilful questioning and well-planned retrieval practice.
This we know, but I have not yet justified why my Y7 pupils have yet to learn about Cells and what all this has to do with Physics!
We’ll get to that!
The following is deliberately meant to read like Yoda explaining the path to the dark side. Enjoy.
The topic of Cells is filled with domain specific knowledge, tier 3 words, complex processes and complex diagrams. Even the humble animal cell is home to respiration, mitochondria, etc. How often have you found yourself saying something like:
“photosynthesis… But you’ll learn more about that in year 8”
“respiration releases energy, more on that next term”
“respiration is a chemical reaction, more on that when we move to chemistry”
Some would argue that you can cover the topic at a surface level. Introducing the form of the Cell, components, functions and then linking the abstract to the concrete. (Tom Sherrington outlines this concept here.) My response is, well yes you could, but if we follow the premise of breaking down learning into smaller steps then we must do so, right down to the most fundamental level.
My argument goes that to FULLY understand an animal cell we must explore Chemical Reactions, Atoms, Energy, Particles and Forces FIRST. Once forces has been mastered, we can then use the terminology and concepts to explore why substances take the form of solids, liquids and gases in the Particle Model. We then delve into the Particle to explore atoms before then using this knowledge to carry out and explain chemical reactions. At this point both endothermic and exothermic reactions can be “fully” explained thanks to their grounding in Energy slotted in-between. Physics provides the first crucial building block in an effective schema that can eventually allow students to articulate the structure and function of a range of cells.
I’ll say it again:
– Forces leads to Particles
– Particles leads to Atoms
– Atoms leads to Energy
– Energy leads to Chemical Reactions
– Chemical Reactions leads to Cells
See? Yoda. (Disclaimer – I am not claiming Biology to be the dark side of the force.)
The switch to a fully common curriculum sequence has had lots of useful side effects beyond schema building including:
- Increased planning discussions / collegiately within the department as more staff work on a topic at the same time.
- Reduced workload as a result of the above.
- Whole class feedback occurs across different classes from a band / year group simultaneously, this has helped to pull out common misconceptions and feed it back into our planning as a team, not just in isolation.
- Assessments can be adapted to match any lag if coverage is slower than expected. Everyone is roughly up to the same point at any one time.
Do I rip everything up and start again?! What about my textbooks?!
The Twitter poll turned into several interesting discussions about what we teach and why we teach it in the order that we do, and this is the truly important part of this. Discussion, thinking and reflection.
If we keep doing what we have always done, then we will get what we have always got.Henry Ford
What is apparent is that context is king. Staffing, funding, whole school timetabling pressures, setting and resourcing all contribute to the decisions that go into the sequencing of science curricula. I do not claim to have all the answers, but I certainly hope I have helped raise some questions about why you teach the sequence that you do.
And keep the textbooks, just don’t feel you have to start at page 5.