A special clock for American Independence Day. It only uses the digit 4.
Can you design a special clock for a different day of the year using a different digit?
Topics: Starter  Arithmetic  Investigations  Problem Solving
This evening, I was at a parents’ evening @NDHSSheffield and this clock was on the wall in one of the maths rooms! #CoolMaths pic.twitter.com/05mSlRVBLF
— Mrs Grant (@MrsGrant_BATL) March 9, 2018
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There are of course many ways pupils might respond to this challenge but here is an example of a solution
$$1=\left(\frac{9}{9}\right)^9$$
$$2=\left(\frac{9+9}{9}\right)$$
$$3=\sqrt{9}+99$$
$$4=\sqrt{9}+\frac{9}{9}$$
$$5=\sqrt{9}!\frac{9}{9}$$
$$6=\sqrt{9}\times\sqrt{9}\sqrt{9}$$
$$7=\sqrt{9}!+\frac{9}{9}$$
$$8=9\frac{9}{9}$$
$$9=9+99$$
$$10=9+\frac{9}{9}$$
$$11=99\div9$$
$$12=9+\frac{9}{\sqrt{9}}$$
This type of challenge has been around for a long time. The first known reference is in a book called "The Schoolmasters Assistant: Being a Compendium of Arithmetic, Both Practical and Theoretical". It was written in 1762 by Thomas Dilworth, an English cleric. Here is the wording as it appeared in the book:
$$33+\frac33 = 34$$
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Have you read Craig's book yet?Craig Barton must surely be the voice of Mathematics teachers in the UK. His wonderful podcasts interviewing the industry experts have culminated in this wonderful book. As Craig says: "I genuinely believe I have never taught mathematics better, and my students have never learned more. I just wish I had known all of this twelve years ago..." more... "How I wish I'd taught Maths" is an extraordinary and important book. Part guide to research, part memoir, part survival handbook, it’s a wonderfully accessible guide to the latest research on teaching mathematics, presented in a disarmingly honest and readable way. I know of no other book that presents as much usable research evidence on the dos and don’ts of mathematics teaching in such a clear and practical way. No matter how long you have been doing it, if you teach mathematics—from primary school to university—this book is for you." Dylan Wiliam, Emeritus Professor of Educational Assessment, UCL. 
Casio Classwiz CalculatorThere is currently a lot of talk about this new calculator being the best in its price range for use in the Maths classroom. The new ClassWiz features a highresolution display making it easier to view numerical formulas and symbols but it isn't a graphical calculator as such (it has the capacity to draw graphs on your smart phone or tablet, via a scannable QR code and an app). As well as basic spreadsheet mode and an equation solving feature you also get the ability to solve quadratic, cubic or quartic polynomial inequalities and the answer is given just as it should be written down, using the correct inequality symbols! This calculator has a highperformance processor and twice the memory of previous models ensuring speedy operation and superior computational power.more... 
Teacher, do your students have
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Here is the link to the pairs game based on AmericanEnglish and BritishEnglish mathematical words.
Transum.org/go/?to=MathvsMaths
Here is a visual aid for teachers to use when teaching alalogue time.