On Threshold Concepts and Experiences


In a recent post, “On Knowledge and Curriculum,” we reviewed a few disruptive ideas from cognitive psychologist Daniel Willingham, with the most incendiary implication being:

a school needs to come to a consensus on the topics, texts, vocabulary, and concepts that are most essential to know within and across each academic domain and carefully sequence and reinforce those concepts across classrooms and grades.

So how can a school embark upon this quest? In this post, I will attempt to provide some guiding ideas and protocols for this work.

How Do We Reinforce Knowledge?

First off, a few guiding documents to equip you with the cognitive principles of affirmative testing, which are essential to reinforcing knowledge over time:

—Annie Murphy Paul, “Affirmative Testing” (she has designed an entire e-course around these concepts!)

—Deans for Impact, “The Science of Learning


How Do We Determine the Knowledge that is ESSENTIAL?

Folks are going to disagree about this, including the “experts,” so ultimately, this determination should be made collaboratively within a school (and beyond). The key is that the school comes to a consensus on this essential knowledge, then teachers carefully sequence it across the curriculum and quiz it repeatedly in a low stakes manner.

There’s a useful frame, known as threshold concepts, for drilling down to this “essential knowledge” within a specific academic domain. Threshold concepts come out of higher ed academia, and it’s admittedly a bit esoteric in the literature, but I think it’s a useful lens with practical implications. Threshold concepts are very much related to Wiggins and McTighe’s “big ideas,” but with a few interesting twists.

I first stumbled over the threshold of these concepts in blogs from UK educators, to whom I’m indebted for starting me on this journey:

—Alex Quigley, “Designing a New Curriculum: What are your ‘Big Ideas?’

—Joe Kirby, “One scientific insight for curriculum design” (he also sums up research on affirmative testing really well here)

What we’re really trying to get here is that 20% of the knowledge that is most essential to understanding an academic domain in a specific grade. Here’s a frame for this:


How can threshold concepts help us to determine that 20% of essential knowledge within a specific academic domain? I decided to review some of the literature for further clues:

—Ray Land, Jan Meyer, and Jan Smith,”Threshold Concepts within the Disciplines” (Land and Meyer are the rockstars who originated the concept)


—James Rhem, “Before and after students “get it”: threshold concepts” (a useful overview)

This idea of a transformation of understanding that is essential for progressing deeper into the academic content is really interesting.


—James Atherton, “How do people ‘get it’?” (another useful overview)

There are many other characteristics that were identified, but they don’t all seem very useful in a practical sense for K-12. I think the three outlined above are the most relevant and applicable.

—Tracy Fortune, Priscilla Ennals, and Mary Kennedy-Jones, “The Hero’s Journey: Uncovering Threshold Barriers, Dispositions, and Practices Among Occupational Therapy Students


I love this idea of viewing a student’s passage through a threshold concept as akin to a hero’s journey. In considering this journey, what are the troublesome obstacles and bottlenecks that student will face? The idea of “bottlenecks” comes thanks for the link immediately below. In thinking through this, I also think we need to acknowledge that bottlenecks may not be purely conceptual — they can also be procedural, in the form of skills required to complete academic tasks, as well as social-emotional (this can be a tremendous and often unaddressed barrier for many kids).

In this sense, then, we can expand the notion of crossing a threshold to not solely refer to concepts, but furthermore experiences. As educators, we seek to design experiences in which students engage in an academic form of a hero’s journey, learning to overcome barriers and gain the intellectual accomplishment of mastering skills and knowledge.

—Joan Middendorf & David Pace, “Decoding the Disciplines: A Model for Helping Students Learn Disciplinary Ways of Thinking” (they offer a useful protocol that I’ve drawn from below)

OK, So How Do We Discover These Threshold Concepts and Experiences?

But we still need some kind of process for distilling away all the cruft and getting down that 20% of the most essential knowledge within a content and grade.

Here in the US, we have a general list of skills we use as guidance in the form of state standards. And as I’ve done with the Common Core standards, we can do a deeper analysis to begin unpacking what that knowledge might be.

But this can still be at a pretty abstract level, and we want this to be relevant to classroom teaching. By focusing on the topics and texts that will be studied, we can make this more concrete.

Because English Language Arts is my specific area of expertise, I’ve focused my efforts in this area, especially since this content area is probably the most difficult to pin down in terms of a progression of knowledge.


There’s two ways we could utilize this protocol: 1) unit of study, or 2) over the entire school year.

1) Consider the topics and/or texts that will be taught.

2) What will be the product or products that students will be expected to create that can demonstrate their mastery of learning? (This product could also be a performance).

3) What are the primary modalities that this product is focused upon? In literacy, of course we’re focused on all modalities, but it helps for a department to focus upon the one they consider most essential.

4) Now consider the standards that your district adheres to. For the Common Core, they are helpfully broken up by modality, so turn to that modality. Then, narrow down which specific, few standards you will primarily be targeting.

5) What are the bottlenecks, most especially those that are conceptual and specific to this content, that students will encounter?

6) Evaluate the list of items you have generated. Do they fit the criteria of a threshold concept or experience? Are they transformative, integrative, and troublesome? If not, they may not be essential.

7) You don’t have to do this, but I find that at this step it can be useful to phrase the threshold concept in the form of a message or lesson, akin to a theme statement.

For example, for an upcoming professional learning session I’m working on about supporting struggling middle school readers, I’ve identified the following threshold concepts:

  • Students that struggle with reading comprehension also often struggle with a lack of academic and world knowledge. An English Language Learner can also be understood as native English speakers that do not understand the language of math, science, social studies – i.e. academic, formal, domain specific language.
  • A teacher must work through a task/text in order to identify key takeaways, key vocabulary, and potential barriers to learning, regardless of whether a curriculum is provided.
  • All learners can be engaged in reading and comprehending complex academic texts through well-designed activities, tasks, and resources.
  • An environment in which a student feels safe to take risks in front of peers is a prerequisite for learning — most especially for struggling readers.
  • Learners should be explicitly equipped with strategies and mindsets for when they encounter challenging vocabulary on their own.

It’s important to note that threshold concepts will vary completely depending on any teacher’s specific set of knowledge, perspectives, and interest, and I think that’s OK. What’s most important is that once these most essential concepts and experiences have been identified and voiced, they will not only help to focus that teacher’s instruction on what they feel is most important, they will serve as a basis for arriving at a consensus as a department and as a school.

Here’s a few really basic examples at a unit level of study:

Now that threshold concepts and experiences have been identified, here’s the really hard part:


This is where the rubber hits the road. This is the part that is so very contrary and disruptive to the norms of public education.


I hope some of these resources in this post are useful to your work. The slides outlined above and the protocol are accessible and downloadable here:

Deaf Space

Some interesting design considerations for design of spaces that can not only provide a better environment for the deaf, but possibly a better environment for all.

Unconscious Bias


We’ve explored the concept of cognitive bias here before, and it’s an important idea to continuously remind ourselves of, as we all are prone to fall prey to problematic thinking each day, given our brain’s reliance on short cuts, heuristics and stereotypes.

Here’s a useful short video from the Royal Society on “Understanding Unconscious Bias” to give you a quick refresher, or introduction, as the case may be:

Further posts here on the topic:

Guest Post: In Defense of Educators

Editor’s Note: More than simply a place to express ourselves, we hope that Schools as Ecosystems can become a forum for conversations between educators about how to build sustainable public schools. We are happy to welcome our first guest blogger, teacher Mike Schirtzer, to this conversation.

Speaking as a native New Yorker from Brooklyn who grew up in poverty, the only thing that saved me from myself was school. It was a place where I learned how to get ahead and develop friendships. I was lucky to have teachers who guided me towards the right path. The sense of security that the teachers were able to provide, along with the constant belief they had in me, challenged me to be a better person. They brought me the success I have today. I hope and pray each day that as a teacher, I too can instill the same drive and enthusiasm in my students.

I certainly did not become a teacher for the money or the benefits; I became a teacher to inspire children the way teachers inspired me when I was in school. We cannot hide behind the fact that there are some appalling teachers and ineffective principals, but how about for once, we highlight the thousands of great ones. These are the kinds of workers you find in my school. They are there early in the mornings, late into the night, weekends, summers, preparing the best lessons they possibly can, always having our students’ best interests at heart. The staff at my school goes out of its way to ensure that there are various extra-curricular activities available for the students, despite all the budget cuts. Now the question is, why do they put in all of this effort, long beyond their work hours?

The answer is a simple one: to ensure that our school is a safe and welcoming environment for students where they want to stay and learn, to develop strong relationships, and participate in activities even after the school day is over. This is important to me personally because some students have no other good place to go. They should not have to rush home and face the realities of poverty and broken families like I did when I was a child.

My colleagues deserve recognition for their dedication and hard work, even though few expect it and all would be embarrassed to receive any credit, because that is not why we show up every morning. I find it sad that a society that once held teachers in high esteem now maligns them on a regular basis. This is not a productive way to lure the best and brightest into our profession. I hope that one day, society as a whole will be able to see past the few that should not have chosen this profession and look at all the unsung heroes.  

I love being a teacher, and work hard at being the best I can possibly be; my colleagues and friends feel the same way. There are many news outlets that belittle and demean us teachers on a daily basis and rarely bother to commend us for the work we do. This in itself is more detrimental to education than the damage that any one teacher can possibly make. We show up to work everyday, under increasing pressure to have students prepare for tests, tests, and more tests— yet despite all the pressure and criticism we endure, when we look into the sea of shining faces that sit in our classrooms, we don’t see test scores. We see the great leaders of tomorrow.

Michael G. Schirtzer
Leon M. Goldstein High School for the Sciences

Planting Seeds

I had a piece published in the NY Times yesterday about teacher evaluation and the experience of being rated “unsatisfactory.” It was exciting to get a piece in the Times, but it was especially exciting that I got to work an ecological metaphor, about teachers “planting seeds,” into the article. Even more exciting was that I got to mention one of my favorite teachers, Ms. Leonard, in the article.

I took Ms. Leonard’s Creative Writing class twice, and then did an independent study with her my senior year of high school. In the article, I describe the impact Ms. Leonard had on me as both a person and a writer:

“I’m thinking about Ms. Leonard, the English teacher who repeatedly instructed me to ‘write what you know,’ a lesson I’ve only recently begun to understand. She wasn’t just teaching me about writing, by the way, but about being attentive to the details of my daily existence. It wasn’t Ms. Leonard’s fault that 15-year-old me couldn’t process this lesson completely. She was planting seeds that wouldn’t bear fruit in the short term.”

This idea of teachers planting seeds is a powerful one to me. First of all, it reflects the fact that learning is a mysterious process. A new idea or concept can lie dormant for a very long time, creating the appearance of barren intellectual ground. Then, suddenly, a green shoot emerges and the student has learned something. It took me years to understand Ms. Leonard’s lessons, but that’s how learning works.

So, think back on the different teachers you had. Did any of them plant seeds that took a long time to blossom? What did they teach you?