# Conception of the good

### Insights into our current education system

#### Month: March 2016

This post will be outlining the academic rigour I have seen in the teaching and in the assessments created by the Uncommon Schools Network. I shall explain how we can develop such rigour in our classrooms as individual teachers.

Each grade (year group) has an interim assessment exam which is determined centrally by a subject lead teacher; although collaboratively made, a subject lead teacher will finalise the exam produced. Once it is finalised, all teachers within the network will have access to view the assessment but will not have the access to make any amendments/alterations.

I was very impressed by the interim assessments made, because they are created in a way in which pupils’ mathematical knowledge is tested in a manner where they are forced to manipulate the knowledge they have: it tests and masters the fine balance between procedural fluency and conceptual understanding in each question. It also made me reconsider how I plan my teaching, how I now combine concepts in different problem types and how I try to make rigourous low-stake quizzes including questions like the ones you are about to see.

I am going to look at one question which I thought was brilliant, then explain how I would plan a selection of lessons, in a sequence, inducing pupils to become mathematically proficient and confident in order to attempt such a question. Here I am assuming by convention from how I was trained and from what I have seen in my experience, previously I would begin by teaching the concept of square numbers and square roots, by getting children to identify the square numbers by multiplying the root number by itself, and then drawing the link: that once you square root a square number you will obtain the initial root number which, multiplied by itself, then results in that square number.

Then, I would have possibly explored completing calculations with square numbers and square roots. After that, in years to come, I would teach square numbers and square rooting in relation to fractional indices and with surds. When teaching surds, I would bring in the idea of rational and irrational numbers. Here is what I now suggest!

This is how I would map out teaching the topic of square numbers, square roots and holding a root number, to an index number greater than 2, and introducing rooting greater than a square root. Kids must have gotten to a stage where such calculations are memorised: Why not bring in the idea of interleaving fractions, decimals etc? Then, I would build upon the previous questions systematically, in a way in which students can create a fraction which can be simplified. Also, I would introduce from an early stage the proposition that when we square root a square number we get positive and negative of the root number, which can be a really valuable discussion to have with children. Introduce calculations afterwards with square numbers and square rooting. This type of thinking is driven by another question I saw in a North Start Academy assessment:  The question is touching on key knowledge that when x is equal to a square root then we assume a positive value as an answer, however when x is held to an exponent the values of x will result in a positive and negative value.

Eventually I would introduce a base number to an exponent greater than 2 and interleave it into calculations: I could get pupils to then go into the following questions: Or, have pupils determine the value of unknowns through trial and error: Now, I am going to draw a link between square numbers, square roots and rational numbers without linking it to fractional indices and surds. The purpose behind this is to (for now) restrict what I would teach at Year 8 or 9 but, at the same time, providing that conceptual scope. Simultaneously, it also provides the opportunity for multiple choice questions that have the academic rigour for our pupils.

I would define a rational number and then go into the necessary vocabulary such as ‘a rational number is a number which can be written as a fraction of two integers. A rational number cannot be written as a non-repeating or non-terminating decimal’, for example, in comparison to 0.45454545 which is a rational number. I would then provide a selection of example and non-examples.

I could test children’s understanding through mini whiteboards or hands up: 1 if it is a rational number and 2 if it is an irrational number; selecting the order of questions such as 2, 6, 100, 15, 1/2 , 5/6, 10/100, then bringing in the square numbers and asking pupils to show why it is a rational number or irrational number such as √16, √36 or √144

Pupils could type in the value of √12 or √3  in a calculator to see that you will get a non-repeating or non-terminating decimal that cannot be written as a fraction of two integers therefore categorising such non examples as irrational numbers.

Also then mentioning that square rooting a square number will result in a rational number, and cube rooting a cube number will result in a rational number etc.

You would then be able to explore the idea of rational numbers in which you are square rooting square numbers using your calculator: Following this, discussion will be made of the notion that the following are rational numbers in regard to the definition of a rational number being a number that can be written as a fraction made of two integers: Then, the idea of either the numerator or denominator being a whole number should be brought into my teaching: After that, I would introduce problem types where you can simplify the fraction: Discuss that the problem below results in an irrational number because the numerator is irrational and overall the solution cannot be written as a fraction of two integers: Will the following number sentences produce rational numbers? Children need to be comfortable in identifying that  is not a rational number because it cannot be displayed as a fraction of two integers. The definitions need to be consistent so that children are confident in differentiating between a rational and irrational number using square numbers and square roots, and then moving onto powers greater than 2. If we expose children to the following above we are providing the academic rigour which future exam boards are attempting to build upon.

All of this is just an idea which I am trying to explore in order to provide students with the academic rigour, in terms of their classwork and in the assessments, that they will be taking. Everything that I have written, the problem types I have created and the interconnections between square numbers, square rooting, and rational numbers, is a result of looking at such questions above. These questions guided me to plan a selection of lessons which provide the balance between enabling students to become procedurally fluent in calculations and in developing conceptual understanding of this topic.

Through creating difficult assessments you can guide your teaching to induce that academic rigour. I have never taught maths like this, but I do plan to in the future. This was all inspired through looking at this question at North Star Academy in New Jersey. The academic rigour present in the interim assessment guides to create academic rigour in what is being taught and learnt within the classroom.

School visited: Uncommon Collegiate Charter High School

Class observed: AP Grade 11 Statistics (UK equivalent Year 13)

Theme of post: Pedagogy and Curriculum

This is the second blog of a series to complement a workshop I delivered at #Mathsconf6  on Mathematics Pedagogy at USA Charter Schools, following my visiting a selection of Uncommon and North Star academy schools in New York and New Jersey. During the workshop, I discussed how the common denominator in each maths lesson I observed was the level of academic rigour. I am still trying to find a way to define this term, because it is overused and poorly defined.

Nevertheless, I believe I can state that the teaching and learning delivered by such extraordinary teachers in the classrooms I observed displayed features of academic rigour. These features of academic rigour are evident in the structure of a teacher’s pedagogy and instruction: In my workshop, I discussed the four main elements that all teachers up and down the country can implement into their teaching practice with minimal effort and maximum impact. I will discuss each of these four elements in turn, by way of one per blog post; today I will discuss the sequence of instruction.

I was observing a lesson, Grade 11 Statistics, and the teacher had organised the lesson so that he was trying to have pupils factorise cubic expressions where one of the expressions in the factorised form could be further factorised into two expressions because one group  was a difference of two squares. (Figure 1) The sequence of instruction to explain to pupils how they can factorise such cubic expressions is what made his lesson so powerful. Figure 1 – Sequence of Instruction in terms of expressions used in teaching

Here, I entered the classroom, and the teacher had displayed the following algebraic expressions that he wanted pupils to factorise. (Figure 2) Before the pupils had even started to factorise he spent some time identifying the common features which determined this expression to be a difference of two squares. It is known as the difference of two squares because we have even powers, square numbers as coefficients and one positive term and one negative term. Figure 2 – Difference of two squares expressions + common features of this type of expression

What I found really fascinating was the examples that he had initially chosen in order to begin teaching pupils how to factorise such expressions. Previously, whilst teaching, I would begin teaching the topic by using the following examples and non-examples to state what the common features of an expression known as a difference of two squares actually looked like, and therefore what it would not look like. Therefore, I utilised simply examples and non-examples. (Figure 3) Figure 3 – Examples and Non examples used in the initial stages of teaching how to identify an expression known as a difference of two squares

The way the teacher started was better, because the expressions he had used made the common features more obvious to pupils. So the initial examples of a difference of two squares that I would have started to teach from are actually more nuanced and special; the coefficient of x2 being 1 is hidden, and instead of having two terms where the variables both have even powers we have a constant which is a square number.

Second, he then introduced the consistent algorithm he wanted pupils to use to go from the expanded form to the factorised form of the expression. He was very systematic (Figure 4 – consistent algorithm):

Step 1: square root both terms;

Step 2: divide both exponents by 2 and

He did this with a selection of examples, as you can see below:

Figure 4 – Consistent algorithm to factorise an expression known as a difference of two squares

Following this, he then introduced the notion that the pupils would now learn how to factorise a cubic expression. At this point in the lesson, I wasn’t fully sure with where he was going (until we reached the end of the lesson). He stated that when we factorise a cubic expression as such we need to factorise the first two terms and the last two terms. He structured it for his pupils because he pre-empted a common mistake that pupils would have made unless he structured it for them. We are factorising the first two terms by dividing both terms by 1, whereas with the last two terms we are going to factorise by -1, because -1 is the greatest common factor of -8p and -24. (Figure 5)  Therefore, the first step of the algorithm is not line 2: it is line 3. This was so powerful because by pre-empting this misconception, and by being very explicit with this instruction and guidance, it made the lesson run more smoothly because pupils were more independent to get on with the practice set of questions – because they weren’t making this mistake. Figure 5 – Structuring the first step of the algorithm

He then carried on to lay out the consistent algorithm between the expanded form and the factorised form.

Step 1: factorise the first two terms, and the last two terms. (be careful when factorising the last two terms)

Step 2: Now factorise the greatest common factor for both terms (ensure that you are factorising the GCF of the coefficients as well as the variables) However, he posed the question one more time: “What is the greatest common factor  of 16p^3 and 48p^2?” Students then noticed that we are no longer factorising by identifying the greatest common factor of the coefficients but also of the variables of each term. (Figure 6) Figure 6 – Step 2 – Step 4 demonstrated

Step 3: factorise the greatest common binomial of the expression:

Again, the algorithm was consistent. Furthermore, he said factorise “the greatest common binomial”. This level of technical language being used in the classroom is fantastic, and is something I certainly intend to implement in my teaching practice.

Step 4: “Are we done with this problem?” he asked this question with the intent of having students identify that the first expression in parenthesis is not fully factorised – which pupils identified.

Here he paused and said to his pupils “Now you are thinking that we are finished because we have two groups that can then be expanded and simplified to form the expanded form which we start with, but we are not finished. What is the greatest common factor of the first group?” However, he posed the question one more time “What is the greatest common factor of 16p^2 and 8 ?”.Pupils then identified this to be 8. He then proceeded to do a selection of examples to complement the first example, and to also reiterate the consistent algorithm. Figure 7

Figure 7 – Further examples of factorising cubic expressions presented in class using a consistent algorithm

Now, this was the pinnacle of the lesson. This was the point where the teacher introduced the next expression to factorise but in doing so he was combining the procedural knowledge of factorising a cubic expression where one of the groups could be factorised because it was a difference of two squares. The sequence of instruction was incredible. Let’s have a look.

Again, he used the consistent algorithm he showed in the previous examples:

Step 1: factorise the first two terms, and the last two terms. Pre-empt that we may be factorising the last two terms by 1 or -1.

Step 2: factorise the greatest common factor of both expressions:

Step 3: factorise the greatest common binomial of the expression.

He asked “can you factorise the greatest common factor of the second binomial? Hands up – what is the greatest common factor of the second binomial?” Pupils confidently answered – “1”. The teacher responded “Excellent, you can display it like this (teacher writes it on the board) and can you do the same on your mini-whiteboards please.” Again, he pre-empted another misconception that the pupils could have potentially made. (Figure 8)  Figure 8 – Structuring a key step in the algorithm where pupils are more likely to make avoidable mistakes though explicit instruction.

Figure 9 – Introducing an expression where one group is an expression known as a difference of two squares

Step 4: factorise the greatest common binomial, which he got above (Figure 9):

He asked pupils to pause. He then asked pupils to look at the problem on the board (the one above). “Can you raise your hand when you can identify what type of binomial expression we have for the first binomial .” Ten hands were raised within the 5 seconds. In total there were 22 hands raised 10 seconds later. Now, after 30 seconds in total following the initial posing of the question, the teacher had an overall 28 out of 32 of pupils’ hands raised. The teacher selects a pupil to state the answer: “Sir, the first binomial is an expression which is a difference of two squares.”

The sequence of instruction here is incredibly effective. What I saw in real time, and what I have outlined for you, is not necessarily profound or extraordinary – on the contrary, it is very simple. It can be performed by all teachers.

It was evident from this lesson that the teacher had put a significant amount of thought into the sequence of his instruction to his pupils. It was well-crafted and sequenced so that all pupils could see the re-iterated key points. What are the characteristics of a problem which is a difference of two squares? What are the characteristics of factorising a non-linear expression? What is the greatest common factor of this expression – ensuring the greatest common factor including coefficients and variables?

I am still working on trying to collate a few different examples in my teaching practice of minimally different examples, and how I have interleaved concepts via sequence of instruction. I shall get back to you on this. Watch this space. Any questions then please do not hesitate to contact me or DM on twitter.

School Visited: Uncommon Collegiate Charter High School

Class Observed: Algebra 1 Grade 9 Statistics (UK equivalent Year 10)

Theme of post: Pedagogy and Curriculum

This is the first blog post in a series complementing a workshop I delivered at Mathsconf6 entitled “Mathematics Pedagogy at USA Charter Schools”. Here I spoke of my experiences whilst visiting a selection of Uncommon and North Star academy schools in New York and New Jersey.

I discussed how the common denominator in each maths lesson I observed was the level of academic rigour in the teaching delivered to pupils. I am still trying to find a way to define this term, because it is overused and poorly defined. However, I do believe I may be able identify the evident features of academic rigour in the structure and delivery of each teacher’s pedagogy and instruction: In my workshop, I discussed four examples of academic rigour that different teachers up and down the country can implement with minimal effort and maximum impact. Each blog post will discuss one example at a time. Today, this blog will address using minimally different examples during instruction. Minimally different examples are examples to explain different concepts where the difference in the algorithm between one concept and the other can be distinguished as one additional step. This was one example I witnessed in one of the classrooms I was in. The teacher presented the first expression to factorise, where the coefficient of a in the quadratic expression is 1. This was a recap exercise where she stated the values for the coefficients, and then she determined the two values of which the product gives us the value of c, and the sum gives us the value of b. She wrote the expression in its factorised form.

She then introduced the next expression to factorise. She stated that it looks visually very different to the first one, but that there is only one difference between the algorithm to factorise the first and second expression. She defined the minimal difference between the two as one additional step – which was at the start of the algorithm. She asked her pupils, “What is the greatest common factor (GCF) of all the terms in the expression?” Pupils spotted the GCF to be 3p, which she then factorised. She said “look, we now have an expression in the parenthesis which looks similar to the first expression we factorised.” The minimal difference between factorising the first and second expression was classified as one additional step. Traditionally, in my training, I would have seen the algorithms to factorise both the expressions as isolated and fragmented. Instead, they are connected; pupils were empowered to factorise more complex expressions from prior knowledge of the algorithm to factorise the first expression. Minimally different examples are a good strategy and example of academic rigour in the classroom because they help pupils to understand knowledge and concepts which are initially complex and ambiguous. Here, the difference between the two examples is classified and determined as one additional step in the algorithm. The possibilities are endless.

I plan to show different examples of how I have used the idea of minimally different examples in my teaching, sometime this week.