This Nrich problem uses the context of sports training to offer opportunities for learners to explore division and/or multiplication. Pupils will be required to consider the relationships between multiplication, division and fractions, which will help reveal their level of understanding.

This is the first Nrich problem in a set of three linked activities. Egyptian Fractions and The Greedy Algorithm follow on.

It's often difficult to find interesting contexts to consolidate addition and subtraction of fractions. This problem offers that, whilst also requiring students to develop and analyze different strategies and explain their findings.

This Nrich activity encourages students to notice and wonder and to engage in mathematical discussions. Students then use graphs to represent the situations.

This Nrich problem encourages children to work together to develop a method for finding a solution which will always work. It will also help to reinforce understanding of odd and even numbers.

This lesson unit is intended to help you assess how well students are able to: Perform arithmetic operations, including those involving whole-number exponents, recognizing and applying the conventional order of operations; Write and evaluate numerical expressions from diagrammatic representations and be able to identify equivalent expressions; apply the distributive and commutative properties appropriately; and use the method for finding areas of compound rectangles.

This is an opportunity for pupils to set up their own models using a spreadsheet and investigate what happens when they change variables such as interest, inflation rates and how much is spent each year. Investigating how a small change in interest rates can affect the total income over different time periods can be enlightening. Investigating the impact of spending large amounts of money up-front can also provide valuable insights.

Students explore in detail how the Romans built aqueducts using arches—and the geometry involved in doing so. Building on what they learned in the associated lesson about how innovative Roman arches enabled the creation of magnificent structures such as aqueducts, students use trigonometry to complete worksheet problem calculations to determine semicircular arch construction details using trapezoidal-shaped and cube-shaped blocks. Then student groups use hot glue and half-inch wooden cube blocks to build model aqueducts, doing all the calculations to design and build the arches necessary to support a water-carrying channel over a three-foot span. They calculate the slope of the small-sized aqueduct based on what was typical for Roman aqueducts at the time, aiming to construct the ideal slope over a specified distance in order to achieve a water flow that is not spilling over or stagnant. They test their model aqueducts with water and then reflect on their performance.

In this Nrich activity, students use manipulatives to investigate triangles. They are asked to construct possible triangles and to search for an impossible combination.

In addition to the purely geometric and trigonometric aspects of the task, this problem asks students to model phenomena on the surface of the earth.

An interactive applet that allows the user to graphically explore the properties of a linear functions. Specifically, it is designed to foster an intuitive understanding of the effects of changing the two coefficients in the function y=ax+b. The applet shows a large graph of a quadratic (ax + b) and has two slider controls, one each for the coefficients a and b. As the sliders are moved, the graph is redrawn in real time illustrating the effects of these variations. Applet can be enlarged to full screen size for use with a classroom projector. This resource is a component of the Math Open Reference Interactive Geometry textbook project at http://www.mathopenref.com.

In this activity, students explore the relationship among angles formed by a transversal and a system of two lines. In particular, they consider what happens when the two lines are parallel versus when they are not.

This short video and interactive assessment activity is designed to teach fifth graders about determining whether various shapes have lines of symmetry.

This is an instructional task that gives students a chance to reason about lines of symmetry and discover that a circle has an an infinite number of lines of symmetry. Even though the concept of an infinite number of lines is fairly abstract, fourth graders can understand infinity in an informal way.

This task provides students a chance to experiment with reflections of the plane and their impact on specific types of quadrilaterals. It is both interesting and important that these types of quadrilaterals can be distinguished by their lines of symmetry.

This task is intended for instruction, providing the students with a chance to experiment with physical models of triangles, gaining spatial intuition by executing reflections.

This Nrich activity is an unusual context in which pupils can consolidate recognizing, finding, naming and writing fractions. The rich environment also gives them the opportunity to identify, name and write equivalent fractions of a given fraction, represented visually as a chain. Furthermore, learners will be adding and subtracting fractions with the same denominators and denominators which are multiples of the same number.

This task can be implemented in a variety of ways. For a class with previous exposure to the incenter or angle bisectors, part (a) could be a quick exercise in geometric constructions,. Alternatively, this could be part of a full introduction to angle bisectors, culminating in a full proof that the three angle bisectors are concurrent, an essentially complete proof of which is found in the solution below.

It starts with the snapping of pictures in everyday objects within the classroom and beyond! Then, with an even closer look, students use Skitch an iOS app to enhance their photos to identify geometric vocabulary terms found in our daily lives.

This problem gives work on percentages in an interesting and challenging way. It also gives you an opportunity to discuss different ways of estimating and therefore shows learners how expressions which look very different can give very close answers.

This instructional task gives students a hands-on experience with composing and decomposing geometric figures.