Education ∪ Math ∪ Technology

Month: November 2016 (page 1 of 1)

Is Teacher Marking Necessary?

Teachers do a lot of marking of student work. But is it necessary?



In this comprehensive review of the literature on feedback, corrective feedback (example shown below) without mechanisms for correcting that feedback were found, unsurprisingly, to have little impact on student learning in most cases.

Wrong answer

An example of minimal feedback


Unfortunately, there is also good evidence (see the same literature review) that taking even more time to add comments to student work does not lead, by itself, to improved student learning. So what can teachers do differently?



Here’s a simple strategy. Take a pile of student work and review it, looking for evidence of student performance, and find examples of feedback that you can meaningfully target to groups of students, and then design activities for the whole class to do that result in different groups of students getting feedback on their ideas. In other words, integrate the time you would spend marking with the time you spend planning but in response to what students did in your class.

One question that comes up when I suggest this strategy to teachers is “But what will I put in my grade-book?” Here I suggest that a grade-book can contain evidence of completion of tasks on a regular basis and that for a smaller number of assignments, more detailed information could be provided. Stopping grading everything doesn’t mean you can’t grade anything; just be more selective. A more radical suggestion is to work at the school-wide level and eliminate everything that isn’t absolutely necessary to improve student learning.


Moving beyond CUBES and keywords

It is well known that children often struggle to solve word problems in mathematics. One strategy that is used to support students with having access to word problems is called CUBES. Another is to have students identify all of the keywords in the problem. (Update: Margie Pearse wrote a longer response to these same two strategies here).


Circle the important quantities, Underline the question, Box any math words, Evaluate: What steps should I take?, Solve and check: Does my answer make sense?


In these strategies, students are encouraged to chunk the information given in the word problem in a variety of different ways. For the CUBES strategy, the word quantities is often defined as numbers including units and direction (if given).

Let’s try out the CUBES strategy with the following word problem from the Mathematics Assessment Project. Why don’t you try it yourself first?

Meal Out


Here is my attempt, as if I were a student, on this task for just the first three of the steps in CUBES.

CUBES with Meal Out


You’ll notice that I have circled a lot of unimportant quantities. I’ve also boxed some math words or expressions that are probably not helpful. These are reasonable things to expect many students to do. How does a child know that “three-course meal” is really a description of a kind of food and not a quantity in this context? We could easily imagine contexts in which the number of courses in a meal is important.

My point is that CUBES is an insufficient strategy to help students have entry to this problem. It might be helpful (sometimes) but it almost certainly not sufficient. There is a lot of thinking yet to be done before identifying the critical information from the problem and being able to solve the problem.


Here are some additional recommendations that you can combine as needed:

  • Make sure students have access to the context itself. In this case, if students do not know what a three-course meal or a two-course meal are, it might be helpful to have pictures or a story that describes these things. If the context is one that you think you will revisit more than once, it may be helpful to act out the story.
  • If you have students who are learning English as a new language, it may be helpful to work out, perhaps with other students in your class, a translation of the context into the language they know best.
  • Have students restate, in a variety of different ways, what they think the context of the situation is about. This will both help students hear different ways of describing the situation and give you information about how students are making sense of the context.
  • Let students ask questions about the context. While solving the problem for students may be counter-productive, answering questions students have about the context will both give you information about how they understand the context and give students helpful information that you may not have predicted they needed.
  • It might be helpful to have students describe the relationships between the quantities and other information given. This might be by drawing a diagram or a mindmap. For a pair of routines that may be helpful here, try Capturing Quantities or Three Reads, both described in this book.
  • After solving the problem as a group and ensuring that everyone understands the solution(s), come back and check which information from the problem was actually useful. Over time this may help students learn how to distinguish the relevant from the irrelevant information in the problem.


Writing Curriculum

An experiment


Let’s try a little experiment. Take a look at the following network graphs and think about what is different for each graph and what is the same for each graph.



Now look at this matrices associated with these network graphs.



Which network graph do you think goes with which matrix and why? (This might take you a few minutes. Be patient.)


This particular task is intended to be used with an instructional routine called Connecting Representations designed by Amy Lucenta and Grace Kelemanik. They describe this instructional routine and three other instructional routines in significant detail in the book they just published, Routines for Reasoning.

One goal of Connecting Representations is to support students in making connections between different mathematical representations which describe the same mathematics but on the surface look very different. Another goal of the routine is to support students in being able to see and describe the mathematical features (or structure) that are important to pay attention to in the individual representations in order to make connections between representations.

In the network graphs, as you no doubt noticed, the number of nodes, the labels for the nodes, the ways arrows are connected between nodes, and the direction of those arrows are all important features. You may have concluded as well that the actual positions of the nodes do not matter. Additionally, by looking at the network graphs and this paragraph, you may also know exactly which parts of the graphs I mean by the word ‘node’ (if not, I mean the circles with the numbers inside).

In the matrices, if you make connections between the graphs and the matrices, you almost certainly had to pay attention to the rows and columns of the matrices and the values of the entries in the matrices, most of which were zeros and some of which were ones.

At a meta-level, you focused on individual parts of each representation, you may have zoomed out to look across different representations, and you made connections between different representations.


Variation theory

I’ve recently been attempting to incorporate a critical idea from variation theory into the design of curricular resources; students learn from noticing differences across a background of sameness, rather than from seeing similar objects and discerning the important features by what is the same across each of the objects. Another way of saying this is that differences stand out much more than similarities do.

On Variation theory, Mun Ling Lo writes:


For the network graphs above, I deliberately varied the connections between nodes and the position of the nodes within the diagram. In the matrices, I represented the connections between nodes and did not represent the position (since I cannot represent the position in a matrix) which resulted in a deliberate variation across the rows and columns.


Tasks that are not really learning tasks

Not all tasks are tasks that students will make new connections from. Some tasks require students to demonstrate understanding of a concept they already know. While it is helpful for students to rethink about ideas periodically as there is significant evidence that this helps students remember ideas over time, we also need to use tasks that build new understanding.

Here’s an example of a task on the same content that assumes students know some mathematical ideas already.


Note that it is impossible for students to do this task without already knowing how to answer both questions. This is not a task that students are likely to learn something new from on its own.

Side note: This is by the most common kind of task I see when I have observed teachers over the past five years.


Instructional efficiency

One strategy for taking a task that serves both purposes of helping students remember things they have learned before and helping students build new connections is to have students practice solving problems but deliberately sequence the problems so that students see new connections between the problems they solve.

For example, try and solve the following mental arithmetic problems in your head, without a calculator, and without writing anything down. While solving these problems, deliberately try to use what you’ve done in an earlier problem to make the next problem easier to solve.


What did you notice yourself doing as you worked through the problems? What big idea might students get out of solving this series of problems?


Ideally you saw that 10 + 3 is the same as 9 + 4 and that may have helped you see 9 + 4 as 9 + 1 + 3 = 10 + 3 so that you could reuse your solution to the previous problem. For 19 + 4, you may have also regrouped to 19 + 1 + 3 = 20 + 3. 29 + 14 may have become 30 + 13 = 43 and 69 + 25 may have become 70 + 24. If not, then if I wanted you to see this, as a teacher I may have had a student who did regroup like this share their strategy with the class.

My point is that I have increased the odds that you saw this regrouping strategy by deliberately choosing the problems for you to try.



If you are designing curriculum or tasks for your students here are my two recommendations:

  1. Pay attention to what you are varying across different problems or representations you give students. What you vary across a group of related problems or representations is what students are more likely to notice.
  2. If possible, do this even when giving students problems to practice so that there is a chance students learn something new from that practice.