60Secondary Teacher Big Button Pagehttp://nrich.maths.org/teacher-secondaryen 2012 http://nrich.maths.org/public/terms.phpFreedom and Constraints in the Classroomhttp://nrich.maths.org/10932Thu, 01 May 2014 00:00:01 +0100Dotty Grids in the ClassroomThis article suggests ways in which a dotty grid can be used in the classroom as an environment for rich explorationhttp://nrich.maths.org/10818Sat, 01 Mar 2014 00:00:01 +0000Estimating TimeHow well can you estimate 10 seconds? Investigate with our timing tool.http://nrich.maths.org/10629Sun, 01 Dec 2013 00:00:01 +0000What's the Weather Like?With access to weather station data, what interesting questions can you investigate?http://nrich.maths.org/10470Tue, 01 Oct 2013 00:00:01 +0100Perception Versus RealityInfographics are a powerful way of communicating statistical information. Can you come up with your own?http://nrich.maths.org/10466Tue, 01 Oct 2013 00:00:01 +0100Picturing the WorldHow can we make sense of national and global statistics involving very large numbers?http://nrich.maths.org/10464Tue, 01 Oct 2013 00:00:01 +0100Up, Down, Flying AroundPlay this game to learn about adding and subtracting positive and negative numbershttp://nrich.maths.org/9941Wed, 01 May 2013 00:00:01 +0100Strange Bank AccountImagine a very strange bank account where you are only allowed to do two things...http://nrich.maths.org/9923Mon, 01 Apr 2013 00:00:01 +0100A Brief Introduction to the Argand DiagramComplex numbers can be represented graphically using an Argand diagram. This problem explains more...http://nrich.maths.org/9859Fri, 01 Feb 2013 00:00:01 +0000A Brief Introduction to Complex NumbersIn this problem, we define complex numbers and invite you to explore what happens when you add and multiply them.http://nrich.maths.org/9858Fri, 01 Feb 2013 00:00:01 +0000Prize GivingWhat's the fairest way to choose 2 from 8 potential prize winners? How likely are you to be chosen?http://nrich.maths.org/9843Fri, 01 Mar 2013 00:00:01 +0000Who Is Cheating?A practical experiment provides data. Moving onto expected results provides a context to establish the multiplication rule in probability, and an intuitive approach to conditional probability.http://nrich.maths.org/9840Tue, 01 Jan 2013 00:00:01 +0000Which Team Will Win?A practical experiment which will introduce students to tree diagrams, and help them to understand that outcomes may not be equally likely.http://nrich.maths.org/9546Tue, 01 Jan 2013 00:00:01 +0000The Dog Ate My Homework!A practical experiment which uses tree diagrams to help students understand the nature of questions in conditional probability.http://nrich.maths.org/9525Tue, 01 Jan 2013 00:00:01 +0000Complex SquaresWhat happens when we square complex numbers? Can the square of a complex number be real?http://nrich.maths.org/8109Fri, 01 Mar 2013 00:00:01 +0000What Numbers Can We Make?Imagine we have four bags containing a large number of 1s, 4s, 7s and 10s. What numbers can we make?http://nrich.maths.org/7405Tue, 01 Feb 2011 00:00:01 +0000Who's the Best?Which countries have the most naturally athletic populations?http://nrich.maths.org/7367Wed, 01 Jun 2011 00:00:01 +0100Always a Multiple?Think of a two digit number, reverse the digits, and add the numbers together. Something special happens...http://nrich.maths.org/7208Tue, 01 May 2012 00:00:01 +0100Dicey OperationsWho said that adding, subtracting, multiplying and dividing
couldn't be fun?http://nrich.maths.org/6606Tue, 01 Feb 2011 00:00:01 +0000Power CountdownIn this twist on the well-known Countdown numbers game, use your knowledge of Powers and Roots to make a target.http://nrich.maths.org/6448Tue, 01 Feb 2011 00:00:01 +0000Power Mad!Powers of numbers behave in surprising ways. Take a look at some of these and try to explain why they are true.http://nrich.maths.org/6401Tue, 01 Feb 2011 00:00:01 +0000WeightsDifferent combinations of the weights available allow you to make different totals. Which totals can you make?http://nrich.maths.org/5958Tue, 01 Feb 2011 00:00:01 +0000Adding and Subtracting Positive and Negative NumbersHow can we help students make sense of addition and subtraction of negative numbers?http://nrich.maths.org/5947Tue, 01 Feb 2011 00:00:01 +0000Playing Connect ThreeIn this game the winner is the first to complete a row of three. Are some squares easier to land on than others?http://nrich.maths.org/5864Tue, 01 Feb 2011 00:00:01 +0000Method in Multiplying Madness?Watch our videos of multiplication methods that you may not have met before. Can you make sense of them?http://nrich.maths.org/5612Sat, 01 Oct 2011 00:00:01 +0100Take Three from FiveCaroline and James pick sets of five numbers. Charlie chooses three of them that add together to make a multiple of three. Can they stop him?http://nrich.maths.org/1866Tue, 01 Feb 2011 00:00:01 +0000Cinema ProblemA cinema has 100 seats. Show how it is possible to sell exactly 100 tickets and take exactly £100 if the prices are £10 for adults, 50p for pensioners and 10p for children.http://nrich.maths.org/1864Tue, 01 Feb 2011 00:00:01 +0000Largest ProductWhich set of numbers that add to 10 have the largest product?http://nrich.maths.org/1785Tue, 01 Feb 2011 00:00:01 +00001 Step 2 StepLiam's house has a staircase with 12 steps. He can go down the steps one at a time or two at time. In how many different ways can Liam go down the 12 steps?http://nrich.maths.org/1019Tue, 01 Feb 2011 00:00:01 +0000