Yesterday I watched English specialists teaching Shakespeare. It was brilliant. The students were able to complete chalenging writing tasks, because their teachers had reduced the cognitive load.
The same strategies work for physics.
What are the cognitive loads of writing and what how can we reduce them?
We can only think about two or three items at one time, so writing is hard. There is a lot to think about. The table below shows three things:
- why writing is a high load activity
- how to reduce load for novice writers
- why expert writers (hopefully your students in a few months) find the load less.
|Load||Reduce the load for novices using…||As students become experts…|
|1||Choosing the relevant knowledge and vocabulary.||Mind map / notes||They will have an automatic recall of relevant knowledge.|
|2||Planning the overall structure of the text – the argument.||Outline plan / sequencing activities (e.g print out the individual ideas for students to sequence).||They will have learn the structures they use most often.|
|3||Planning short sequences of text – a couple of sentences to make a point.||Bullet points / sentence sequencing activities.||Students will have learnt model sequences for key explanations.|
|4||Structuring individual sentences.||Sentence starters / write-rewrite.||Students will have learnt a bank of model physics sentences.|
|5||Spelling, punctuation and grammar.||Teach model sentences / remind students how to punctuate / practice punctuating sentences correctly.||They will have learnt how to punctuate complex causal sentences (these won’t necissarily have been learnt in English lessons).|
Below is an analysis of the cognitive load imposed by a standard physics question.
Explain why a skydiver reaches terminal velocity.
- Key knowledge:
- air resistance
- velocity increases
- resultant force decreases
- balanced forces
- terminal velcity
- At first – no motion
- Speed increases…
- Until terminal velocity
- Sequence of sentences:
- v = 0, acceleration due to gravity. No air resistance.
- v increases → air resitistance increases → resultant force decreases → acceleration decreases.
- v = forces balance → acceleration = 0 → terminal velocity.
- Key sentences:
- Initially, the velocity is zero, so the air resistance is zero and the skydiver accelerates.
- As the velocity increases, so does the air resistance, resulting in a decreased acceleration.
- When the air resistance balances the force due to gravity, the acceleration reaches zero – this is the skydiver’s terminal velocity.
- SpaG check.
How to Teach Writing in Physics…
CLT has revealed several useful techniques which apply to writing:
- Start with model answers. @greg_ashman recommends modelling followed by near identical problems for students to complete (here).
- Use completion problems: choose which of the type of load in the table you want your students to focus on and reduce the rest.
- Gap fills, sentence starters and mind maps are effective techniques for reducing cognitive load. Later you will want to demonstrate combining the different elements into a coherent piece of writing.
- Write/rewrite – the Reading Reconsidered technique (see @doug_lemov) is especially effective in reducing cognitive load when writing complex scientific sentences.
- Reduce support – as the student develops, reduce the support. In fact, supporting an expert can make the cognitive load higher as she tries to negotiate her own knowledge and the support you are trying to give (which is why trying some of these strategies out on colleagues doesn’t work – you have to try them on novices).
If you want to see this all in action, go see a lesson on Shakespeare.