A complete lesson on the theorem that angles in the same segment are equal. I always teach the theorem that the angle at the centre is twice the angle at the circumference first (see my other resources for a lesson on that theorem), as it can be used to easily prove the same segment theorem. Activities included: Starter: Some basic questions on the theorems that the angle at the centre is twice the angle at the circumference, and that the angle in a semi-circle is 90 degrees, to check pupils remember them. Main: Slides to show what a chord, major segment and minor segment are, and to show what it means to say that two angles are in the same segment. This is followed up by instructions for pupils to construct the usual diagram for this theorem, to further consolidate their understanding of the terminology and get them to investigate what happens to the angle. A ‘no words’ proof of the theorem, using the theorem that the angle at the centre is twice the angle at the circumference. Missing angle examples of the theorem, that could be used as questions for pupils to try. These include more interesting variations that incorporate other angle rules. A set of similar questions with a progression in difficulty, for pupils to consolidate. Two extension questions. Plenary: A final set of six diagrams, where pupils have to decide if two angles match, either because of the theorem learnt in the lesson or because of another angle rule. Printable worksheets and answers included. Please do review if you buy as any feedback is greatly appreciated!

A complete lesson for first teaching about corresponding, alternate and supplementary angles. Activities included: Starter: Pupils measure and label angles and hopefully make observations and conjectures about the rules to come. Main: Slides to introduce definitions, followed by a quiz on identifying corresponding, alternate and supplementary angles, that could be used as a multiple choice mini-whiteboard activity or printed as a card sort. Another diagnostic question with a twist, to check pupils have grasped the definitions. Examples followed by a standard set of basic questions, where pupils find the size of angles. Examples/discussion questions on spotting less obvious corresponding, alternate and supplementary angles (eg supplementary angles in a trapezium). A slightly tougher set of questions on this theme, followed by a nice angle chase puzzle and a set of extension questions. Plenary: Prompt for pupils to see how alternate angles can be used to prove that the angles in a triangle sum to 180 degrees. Printable answers and worksheets included. Please review if you buy as any feedback is appreciated!

A complete lesson on the theme of using Pythagoras’ theorem to look at the distance between 2 points. A good way of combining revision of Pythagoras, surds and coordinates. Could also be used for a C1 class about to do coordinate geometry. Activities included: Starter: Pupils estimate square roots and then see how close they were. Can get weirdly competitive. Main: Examples and worksheets with a progression of difficulty on the theme of distance between 2 points. For the first worksheet, pupils must find the exact distance between 2 points marked on a grid. For the second worksheet, pupils find the exact distance between 2 coordinates (without a grid). For the third worksheet, pupils find a missing coordinate, given the exact distance. There is also an extension worksheet, where pupils mark the possible position for a second point on a grid, given one point and the exact distance between the two points. I always print these worksheets 2 per page, double sided, so without the extension this can be condensed to one page! It may not sound thrilling, but this lesson has always worked really well, with the gentle progression in difficulty being enough to keep pupils challenged, without too much need for teacher input. Printable worksheets and answers included. Please review if you buy as any feedback is appreciated!

A complete lesson on prime factors. Intended as a challenging task to come after pupils are familiar with the process of expressing a number as a product of prime factors (see my other resources for a lesson on this). Activities included: Starter: Questions to test pupils can list all factors of a number using factor pairs. Main: Pupils find all factors of a number using a different method - by starting with the prime factor form of a number and considering how these can be combined into factor pairs. Links well to the skill of testing combinations that is in the new GCSE specification. Possible extension of pupils investigating what determines how many factors a number has. Plenary: A look at why numbers that are products of three different primes must have 8 factors. No worksheets required and answers included throughout. Please review it if you buy as any feedback is appreciated!

This started as a lesson on plotting coordinates in the 1st quadrant, but morphed into something much deeper and could be used with any class from year 7 to year 11. Pupils will need to know what scalene, isosceles and right-angled triangles are to access this lesson. The first 16 slides are examples of plotting coordinates that could be used to introduce this skill, or as questions to check pupils can do it, or skipped altogether. Then there’s a worksheet where pupils plot sets of three given points and have to identify the type of triangle. I’ve followed this up with a set of questions for pupils to answer, where they justify their answers. This offers an engaging task for pupils to do, whilst practicing the basic of plotting coordinates, but also sets up the next task well. The ‘main’ task involves a grid with two points plotted. Pupils are asked to plot a third point on the grid, so that the resulting triangle is right-angled. This has 9 possible solutions for pupils to try to find. Then a second variant of making an isosceles triangle using the same two points, with 5 solutions. These are real low floor high ceiling tasks, with the scope to look at constructions, circle theorems and trig ratios for older pupils. Younger pupils could simply try with 2 new points and get some useful practice of thinking about coordinates and triangle types, in an engaging way. I have included a page of suggested next steps and animated solutions that could be shown to pupils. Please review if you buy as any feedback is appreciated!

A complete lesson on patterns of growing shapes that lead to quadratic sequences. See the cover image to get an idea of what I mean by this. Activities included: Starter: A matching activity relating to representation of linear sequences, to set the scene for considering similar representations of quadratic sequences, but also to pay close attention to the common sequences given by the nth term rules 2n and 2n-1 (ie even and odd numbers), as these feature heavily in the lesson. Main: A prompt to give pupils a sense of the intended outcomes of the lesson (see cover image). An extended set of examples of shape sequences with increasingly tricky nth term rules. The intention is that pupils would derive an nth term rule for the number of squares in each shape using the geometry of each shape rather than counting squares and finding an nth term rule from a list of numbers. A worksheet with a set of six different shape sequences, for pupils to consider/discuss. The nth term rules have been given, so the task is to justify these rules by considering the geometry of each shape sequence. Each rule can be justified in a number of ways, so this should lead to some good discussion of methods. Plenary: Ideally, pupils would share their differing methods, but I’ve shown a few methods to one of the sequences to stimulate discussion. Printable worksheets (2) included. Please review if you buy as any feedback is appreciated!

A complete lesson on identifying the y-intercept of a linear function. Intended as a precursor to using gradient and y-intercept to plot a linear function, but after pupils have plotted graphs with a table of values (ie they have seen equations of lines already). A good way of getting pupils to consider gradient without formally being ‘taught’ it. Activities included: Starter: A puzzle about whether two boats (represented on a grid) will collide. Main: Examples and three worksheets on the theme of identifying y-intercept. The first could just be projected and discussed - pupils simply have to read the number off the y-axis. The second is trickier, with two points marked on a grid, and pupils extend this (by counting squares up and across) until they reach the y-axis. The third is a lot more challenging, with the coordinates of 2 points given on a line, but no grid this time (see cover image). Could be extended by giving coordinates of two points, but one either side of the y-axis (although I’m going to do a whole lesson on this as a context for similarity, when I have time!) Plenary: A look at how knowing the equation of a line makes finding the y-intercept very easy. Examples, printable worksheets and answers included. Please review it if you buy as any feedback is appreciated!

A complete lesson on a mixture of area and circumference of circles. Designed to come after pupils have used area and circumference rules forwards (eg to find area given radius) and backwards (eg to find radius given area). Activities included: Starter: Questions to check pupils are able to use the rules for area and circumference. Main: A set of four ‘mazes’ (inspired by TES user alutwyche’s superb spider puzzles) with a progression in difficulty, where pupils use the rules forwards and backwards. A ‘3-in-a-row’ game for pupils to compete against each other, practicing the basic rules. Plenary: Questions to prompt a final discussion of the rules. Printable worksheets and answers included. Please review if you buy as any feedback is appreciated!

A complete lesson or maybe two, where pupils consider how perimeter varies for rectilinear shapes. Sounds simple but it involves pupils investigating and using algebra to form and solve equations. Designed to follow on from another lesson I’ve put on the TES website about perimeter, although it works as a stand alone lesson too. Activities included: Starter: A quick task to get pupils thinking about when perimeter varies and when it doesn’t. Main: Three similar-but-different scenarios for pupils to investigate, by drawing different shapes that fulfil given criteria, before trying to spot patterns and generalise about perimeter. One of these scenarios is a ‘non-example’, in that the exact perimeter cannot be found. These scenarios are each formalised using some basic algebra, to model how to approach the next task. I’ve also attached a Geometer’s Sketchpad file which has these questions shown dynamically. If you don’t have GSP, no problem, as I have endeavoured to show the same information within the powerpoint. A set of related perimeter questions, requiring pupils to form simple equations to answer. Includes a few more non-examples, to help deepen pupils’ understanding of the algebra involved. Plenary: A prompt for pupils to reflect on the subtly different ways algebra has been used within the lesson. Printable worksheets and answers included. Please review if you buy as any feedback is appreciated!

A complete lesson designed to introduce the concept of an equation. Touches on different equation types but doesn’t go into any solving methods. Instead, pupils use substitution to verify that numbers satisfy equations, and are therefore solutions. As such, the lesson does require pupils to be able to substitute into simple expressions. Activities included: Starter: A set of questions to check that pupils can evaluate expressions Main: Examples of ‘fill the blank’ statements represented as equations, and a definition of the words solve and solution. Examples and a worksheet on the theme of checking if solutions to equations are correct, by substituting. A few slides showing some variations of equations using carefully selected examples, including an equation with no solutions, an equation with infinite solutions, simultaneous equations and an identity. A sometimes, always never activity inspired by a similar one form the standards unit (but simplified so that no solving techniques are required). I’d use the pupils’ work on this last task as a basis for a plenary, possibly pupils discussing each other’s work. Printable worksheets and answers included. Please review if you buy as any feedback is appreciated!

A complete lesson on solving equations of the form sinx = a, asinx = b and asinx + b = 0 (or using cos or tan) for any range. Designed to come after pupils have spent time solving equations in the range 0 to 360 degrees, and are also familiar with the cyclic nature of the trigonometric functions. See my other resources for lessons on these topics. I made this to use with my further maths gcse group, but could also be used with an A-level class. Activities included: Stater: A set of 4 questions to test if pupils can solve trigonometric equations in the range 0 to 360 degrees. Main: A visual prompt to consider solutions beyond 360 degrees. followed by a second example (see cover image) that will lead to a “dead-end” for pupils. Slides to define principal values for sine, cosine and tangent, followed by a summary of how to solve equations for any range. Three example problem pairs to model methods and then get pupils trying. Includes graphical representations to help pupils understand. A worksheet with a progression in difficulty and a challenging extension to create equations with a required number of solutions. Plenary: A prompt to discuss solutions to the extension task.

A complete lesson on the theme of star polygons. An excellent way to enrich the topic of polygons, with opportunities for pupils to explore patterns, use notation systems, and make predictions & generalisations. No knowledge of interior or exterior angles needed. The investigation is quite structured and I have included answers, so you can see exactly what outcomes you can hope for, and pre-empt any misconceptions. Pupils investigate what happens when you connect every pth dot on a circle with n equally spaced dots on their circumference. For p>1 this generates star polygons, defined by the notation {n,p}. For example, {5,2} would mean connect every 2nd dot on a circle with 5 equally spaced dots, leading to a pentagram (see cover image). Pupils are initially given worksheets with pre-drawn circles to explore the cases {n,2} and {n,3}, for n between 3 and 10. After a chance to feedback on this, pupils are then prompted to make a prediction and test it. After this, there is a set of deeper questions, for pupils to try to answer. If pupils successfully answer those questions, they could make some nice display work! To finish the lesson, I’ve included a few examples of star polygons in popular culture and a link to an excellent short video about star polygons, that references all the ideas pupils have considered in the investigation. I’ve included key questions and other suggestions in the notes boxes. Please review if you buy as any feedback is appreciated!

A complete lesson on the theorem that tangents from a point are equal. Assumes pupils can already use the theorems that: The angle at the centre is twice the angle at the circumference The angle in a semicircle is 90 degrees Angles in the same same segment are equal .Opposite angles in a cyclic quadrilateral sum to 180 degrees A tangent is perpendicular to a radius Angles in alternate segments are equal so that more varied questions can be asked. Please see my other resources for lessons on these theorems. Activities included: Starter: Instructions for pupils to discover the theorem, by drawing tangents and measuring. Main: Slides to clarify why this theorem usually involves isosceles triangles. Related examples, finding missing angles. A set of eight questions using the theorem (and usually another theorem or angle fact). Two very sneaky extension questions. Plenary: An animation of the proof without words, the intention being that pupils try to describe the steps. Printable worksheets and answers included. Please review if you buy, as any feedback is appreciated!

A complete lesson with a focus on angles as variables. Basically, pupils investigate what angle relationships there are when you overlap a square and equilateral triangle. A good opportunity to extend the topic of polygons, consider some of the dynamic aspects of geometry and allow pupils to generate their own questions. Prior knowledge of angles in polygons required. Activities included: Starter: A mini-investigation looking at the relationship between two angles in a set of related diagrams, to recap on basic angle calculations and set the scene for the main part of the lesson. Main: A prompt (see cover image) for pupils to consider, then another prompt for them to work out the relationship between two angles in the image. A slide to go through the answer (which isn’t entirely straight forward), followed by two animations to illustrate the dynamic nature of the answer. A prompt for pupils to consider how the original diagram could be varied to generate a slightly different scenario, as a prompt for them to investigate other possible angle relationships. I’ve not included answers from here, as the outcomes will vary with the pupil. The intention is that pupils then investigate for themselves. Plenary: Another dynamic scenario for pupils to consider, which also reinforces the rules for the sum of interior and exterior angles. Please review if you buy as any feedback is appreciated!

A complete lesson on the theme of balancing equations. There is no solving involved, and the idea is that this lesson would come before using balancing to solve equations. Activities included: Starter: Pupils are presented with a set of number statements (see cover slide) and then prompted to discuss how each statement has been obtained. Pupils then create a similar diagram with an initial number statement of their choice, then could swap/discuss with another student. Main: Pupils are shown an equation and try to create other equations by balancing. They can use substitution to verify whether their new equations are valid. I would follow this up with a whole-class discussion to clarify any misconceptions. Four sets of equations that have been obtained by balancing, pupils have to identify what has been done to both sides each time. A ‘spot the mistake’ worksheet which incorporates the usual misconceptions relating to manipulating and balancing equations. Plenary: A taster of balancing being used to solve equations. Possible key questions, follow up and extension questions included in notes boxes at bottom of slides. Please review if you buy as any feedback is appreciated!

An open-ended lesson on number pyramids, with the potential for pupils to practice addition and subtraction with integers, decimals, negatives and fractions, form and solve linear equations in two unknowns and create conjectures and proofs. I used this lesson for an interview and got the job, so it must be a good one! The entire lesson is built around the prompt I’ve uploaded as the cover slide. I have provided detailed answers for some of the responses that pupils could give, so you can get a clear idea of how the investigation might progress. I would spend the lesson responding to pupils’ work and questions, and probably get pupils to make posters of their findings or discuss their work with other pupils. Suitable for a range of abilities. Please review if you buy as any feedback is appreciated!

A complete lesson on number pyramids, with an emphasis on pupils forming and solving linear equations. An excellent way of getting pupils to think about equations in an unfamiliar setting, and to create their own questions and conjectures. Activities included: Starter: A mini-investigation on three-tier number pyramids, to set the scene. One combination is best dealt with using a linear equation, and sets pupils up to access the more challenging task to come. Main: A prompt for pupils to consider four-tier number pyramids. Although this task has the potential to be extended in different ways, I have provided an initial focus and provided some responses that pupils could give, so you can get a clear idea of how the investigation might progress. I would spend the rest of the lesson responding to pupils’ work and questions, and probably get pupils to make posters of their findings or discuss their work with other pupils. Please review if you buy as any feedback is appreciated!

At least a lesson’s worth of activities on the theme of quadratic sequences. Designed to come after pupils have learnt the basics (how to use and find an nth term rule of a quadratic sequence). Gives pupils a chance to create their own examples and think mathematically. There are four activities included: Activity 1 - given sets of four numbers, pupils have to order them so that they form quadratic sequences. Designed to deepen pupils understanding that the terms in a quadratic sequences don’t necessarily always go up or down. Activities 2 and 3 - on the same theme of looking at the sequences you get when you pick and order three numbers of choice. Can you always create a quadratic sequence in this way? What if you had four numbers? Could be used to link to quadratic functions. Activity 4 - inverting the last activity, can pupils find possible values for the first three terms and a rule, given the fourth term? A chance for pupils to generate their own examples and possibly do some solving of equations in more than one variable. Where applicable, worked answers provided.

A complete lesson on the graph of tangent from 0 to 360 degrees. I’ve also made complete lessons on sine and cosine from 0 to 360 degrees and all three functions outside the range 0 to 360 degrees. Designed to come after pupils have been taught about the ratios sine, cosine and tangent in the context of right-angled triangle trigonometry, and have met the unit circle definitions of sine and cosine. Activities included: Starter: A quick set of questions on finding the gradient of a line. This is a prerequisite to understanding how tan varies for different angles. Main: An example to remind pupils how to find an unknown angle in a right-angled triangle using the tangent ratio, followed by a set of similar questions. The intention is that pupils estimate using the graph of tangent rather than using the inverse tan key on a calculator, to refamiliarise them with the graph from 0 to 90 degrees. Slides to define tan as sin/cos and hence as gradient when using the unit circle definition. A worksheet where pupils construct the graph of tan from 0 to 360 degrees (see cover image). A set of related questions, where pupils use graph and unit circle representations to explain why pairs of angles have the same tan. Pupils can be extended further by making and proving conjectures about pairs of angles whose tans are equal. Plenary: An image to prompt discussion about the “usual” definition of tangent (using the terminology opposite, adjacent and hypotenuse) and the fuller definition (using the unit circle) Printable worksheets and answers included. Please review if you buy as any feedback is appreciated!