Schema & Spiderman

Schemas are categories of information stored in long-term memory. A schema contains groups of linked memories, concepts or words. For example, what things come to your mind when you read the word “viscosity“. If you drew a blank, like most of us, or have a fuzzy recall of the definition - it’s because your brain has not developed enough neural connections to make a strong schema for ‘viscosity’.

The definition of viscosity, as per Britannica, is “viscosity, resistance of a fluid (liquid or gas) to a change in shape, or movement of neighboring portions relative to one another.”

If you were to present this definition to 12 year olds, they would still draw a blank (as would most adults), this is because we don’t have a prior context for it; therefore our brain has to put more cognitive effort or energy to read the definition and comprehend it.

It’s important for teachers or instructional designers to understand the role of ‘schema’, because it can help us implement strategies to reduce the cognitive effort on the brain and make learning easy and less stressful for learners.

Let’s look at how we can help students build a schema for ‘viscosity’.?

Have you ever tried pouring ketchup from a bottle that's almost finished? The thick ketchup settles at the bottom of the bottle, and oftentimes, we need to shake the bottle or tap the bottom to get the ketchup out. Does this ever happen with a bottle of water?

Ketchup and water are both liquids, so why does this not happen with a bottle of water? What is the noticeable difference between ketchup and water?

Water has a low or "thin" viscosity, while ketchup has a "thick" or high viscosity. Viscosity, the "thickness" of fluid, refers to how resistant a fluid is to movement through it.

By using the ketchup bottle example, we are activating a prior knowledge or schema that the student already has. This is an example of providing “context” to activate schema. Pouring ketchup out of a bottle is a known context to students, their brain ‘recognises’ the information as something they already know or have experienced, thus requiring minimum effort to comprehend it.

Can you think of other liquids that exhibit the same viscosity as ketchup? Honey, olive oil, liquid soap, maple syrup and paint are a few such examples.

By providing additional examples, we are “lighting up” additional schemas and helping the brain connect the concept of “viscosity” to these existing schemas. When we help students activate prior schema, we are helping them build more neural connections, thus making the schema for ‘viscosity’ stronger. You can also provide ‘non-examples’ at this point - non-examples help correct any misconceptions that students may have.

In future, when learners try to “recall” what viscosity is, multiple references or schemas (ketchup, honey, olive oil, maple syrup) will light up, helping them, easily recall the meaning of the word.

Let’s go back to the classroom & continue building the schema.

Why does tapping the bottle make the ketchup flow easily?

When you shake the bottle or tap it, you are essentially shearing the molecules in the ketchup, which decreases the viscosity. The biopolymer chains stretch and become disentangled, this enables them to slip away from each other, and that’s why they can come out of the bottle.

Some liquids behave differently when stress is applied (application of force). Shear thickening liquids increase in viscosity as stress increases. Shear thinning liquids decrease in viscosity as stress increases. Ketchup is a shear thinning liquid.?

Did you know? Spider-man’s synthetic web fluid is described as “a shear-thinning liquid” that “on contact with air, the long-chain polymer knits and forms an extremely tough, flexible fiber.” (Science behind Spiderman's powers)

After activating an existing schema, we should continue building on it, preferably, within the same context. Staying focussed in the same context requires less effort on the brain, than switching to a new context and trying to associate the learning from context A to context B.

Adding the Spiderman fact, brings in an “AHA” moment. If student attention was fading away at this point, presenting the Spiderman fact will definitely bring it back & they will be ‘curious’ to know more.?

Teachers can use this as an opportunity to engage students in ‘active learning’, because now they understand what viscosity means & they can relate it to a spider web. When students engage in reasoning and higher order thinking skills, it further strengthens their schema.

Strong instructional design involves thinking about the “neural connections” you want your students to develop. Ask yourself ‘what do learners already know’ or ‘what is the new concept similar to’ and use these insights to plan the starting point & develop the schema web for your lessons.