Principles of Engelmann's Direct Instruction: Overtisation

This post is part of a series where I go in to detail on some of the main aspects of Direct Instruction as laid out by Siegfried Engelmann in this book.

Below are links to the other posts in this series. Scroll past them to read the article.

• Atomisation
• Overtisation
• Expansion and Context Shaping
• Cognitive load
• Review
• Lesson structure and schemes of work
• Speed principle
• Difficulty and Motivation
• Defining range/scope
• Categories for different types of knowledge
• Instruction for basic types of knowledge
• Instruction for linked types of knowledge
• Instruction for routines
• Instruction for problem solving techniques
• "Real world" maths
• Prompts and scaffolding
• Correcting mistakes
• My take on the strengths and weaknesses of Direct Instruction

Overtisation:

Overtisation means giving a visible outcome to every cognitive decision students need to make. This goes further than the standard steps students are usually asked to write to "show their working". These visible outcomes could be oral, written or physical but they must be 'assessable' in that they show you whether a student is understanding that step. There are two reasons to do this:

• Students get a visual or physical hook to remind themselves of what they need to do next. This allows students to get a 'feel' for when they are doing the right steps (much like you do when learning a physical skill like throwing).
• The teacher gets clear indications of exactly when and where students are making mistakes.

Fading:

After the steps have been embedded in to a cognitive routine and the cognitive routine has been developed to a good level of understanding, you allow the students to 'covertise' these steps. This means they start to show less and less working to the point of minimal model answers. This is necessary to keep the pace up for later practice/assessment.

Example:

Before answering  , students:

• first read out the question (to assess understanding of the symbols for multiplied fractions) 
• write:   to show what operations they will perform.

Once embedded, students would remove these steps and go straight to an answer.

It is worth noting that Engelmann often goes way further than this, having 10 whole steps to complete when 7 + 3 is the question!

Unanswered Questions:

Here are a few reflections I have had about covertisation that I still do not have the answer to:

• How far do you go? 10 steps for single-digit addition seems like overkill, but maybe wouldn't be for some classes. My guess is that this comes down to teacher judgement.
• When do you covertise? Engelmann goes in to some detail, but it is not clear to me how I judge this for a whole class. Again, at the moment I am using my personal judgement.
• There is a trade-off between overtisation and speed of practice: the more steps you take, the longer you spend on each question. This surely needs to be considered when thinking about doing it.

By the way, you may be thinking "what about unassessable skills, like critical thinking and decision making? Does DI fall short of teaching these things?" I will be addressing this in the instruction for problem solving techniques section.