5 Maths Gems #20

Hello. I'm pleased to introduce my 20th gems post today - a milestone! Twitter has been repose this calendar week because Christmas took our minds off operate for a duet of days, but I've even therefore got around corking ideas for you. The Christmas holidays are brusk in addition to busy therefore it won't live on long earlier you're dorsum to planning lessons - I promise this post gives y'all around inspiration for the Spring term.

1. Factorising Quadratics
You know questions like this:
In Question 1 above, y'all tin come across that the move past times left jail mobile telephone has to comprise a three because it's a constituent of both three in addition to 6. The residue of the cells tin live on completed speedily i time i mutual constituent has been established. This is a uncomplicated instance but Don develops the questions to acquire increasingly difficult, around having multiple solutions. 

The adjacent ready of activities extend the same see to algebra, starting alongside this:
There's lots of these to consummate - first-class exercise of factorising linear expressions.

The adjacent phase of this exercise is factorising quadratics.
Conveniently I'm currently planning a Year 10 lesson on factorising quadratics. I desire my students to create a lot of exercise therefore volition definitely live on using this activity. The questions construct upwards to a suitably challenging marking of difficulty, ending alongside this one:
I desire to encourage my students to factorise 'harder' quadratics (ie a > 1) past times inspection. This is my preferred method (ie 'guess in addition to test') but my students ever need that I instruct them a to a greater extent than structured approach (eg 'the Grouping Method') which frustrates me. Their insistence on next an algorithm suggests a lack of confidence. I mean value the enquiry higher upwards turns factorising quadratics into a sort of logic problem. Tackling this enquiry without an algorithm mightiness aid my students prepare the confidence to factorise harder quadratics past times inspection.

One final see for a lesson on factorising quadratics - I similar the work below from openmiddle.com. There are a unwrap of possible solutions therefore y'all could challenge students to discovery a dissimilar solution to the someone adjacent to them. 

2. Angle Sense alongside the Interactive Whiteboard
I've been planning a Year vii lesson on angles inwards which I'd similar my students to approximate angle sizes. If y'all were asked to to clitoris an angle of 210o freehand, how would y'all create it? I'd mean value of it every bit a direct delineate of piece of work addition a 3rd of a right-angle. If y'all choose proportional reasoning skills in addition to therefore it's pretty slow to brand an educated guess. An angle estimation activity would operate perfectly good without technology (read out a serial of angle sizes in addition to inquire your students to clitoris their freehand estimates on paper. They in addition to therefore banking firm represent their estimates using a protractor - around other useful skill). But if y'all desire a similar activity for the interactive whiteboard in addition to therefore y'all mightiness similar this fun here. Some of these angle games are quite funny - Banana Hunt in exceptional made me chuckle.
If y'all similar these interactive whiteboard games in addition to therefore you'll discovery loads at Sheppard Software. It's amusing that there's an Absolute Value Number Balls game - this concept isn't covered until Year thirteen inwards the U.K. but I bet my students would beloved to play this game - 5 minutes lite relief inwards a C3 lesson!
FlashMaths.co.uk is around other corking website for interactive whiteboard activities. Flash Maths was created past times Jonathan Hall (@studymaths) who brings us a plethora of fantastic tools on StudyMaths.co.uk. If y'all haven't seen it before, banking firm represent out MathsBot.com which is his uncomplicated (but brilliant) worksheet generator.

3. Big Questions
Billy Adamson (@Billyads_47) shared a fantastic ready of mathematical thinking prompts 'The Big Questions'. Here's a few examples: 


Lovely opened upwards questions from Billy to generate give-and-take in addition to prepare understanding. There's around to a greater extent than adept examples of opened upwards questions here:



4. Trigonometric Problem Solving
Our Year 13s' work solving skills are tested when they're asked to simplify expressions involving trigonometric identities inwards C3 (like the example below).
I discovery that my students acquire frustrated when they can't location a 'way in' direct away. They surrender quickly. There's genuinely a pretty criterion ready of starting points, every bit described on www.intmath.com (@intmath). 

I combat to aid my students experience confident inwards tackling these problems, therefore I genuinely similar this activity from @mjfenton. Here's an extract:
The see is that nosotros starting fourth dimension alongside a lot of construction in addition to gradually give fewer hints until students are able to solve the problems themselves. The steps mightiness appear logical to us, but we're experienced work solvers. 

It's a adept see for maths teachers to seek to solve unfamiliar problems every instantly in addition to and therefore (like the instance below from ‏@dannytybrown) to remind ourselves that mathematical work solving oftentimes requires patience, inventiveness in addition to multiple attempts. We all experience frustration inwards work solving, only similar our students do, but nosotros know that the satisfaction of eventually finding the solution is good worth it.

5. Dividing alongside Decimals
I've mentioned earlier that I beloved MathsPad's resources - enough of them are costless in addition to the residue come upwards at a toll of exclusively £3 per month. Whether your schoolhouse subscribes or not, it's worth registering for e-mail updates inwards lodge to continue runway of all the novel resources. This month, the interactive resources on Decimal Calculations caught my eye. It ever surprises me how many students volition happily tell that xl divided past times ½ equals 20. Activities similar the i shown below volition aid tackle this misconception in addition to encourage students to mean value earlier they answer.

That's it for this week. I'll exit y'all alongside a video from 1977 - 'Congruent Triangles' past times Bruce in addition to Katharine Cornwell (another jewel found on @MathMunch). Happy New Year!