Equations and Formulae - Key Stage 3
This collection of resources supports the teaching of Equations and Formulae.
Here are some of the favourite activities selected by the NRICH team.
- Your Number Was… Think of a number and follow my instructions. Tell me your answer, and I'll tell you what you started with! Can you explain how I know?
- Temperature Water freezes at 0°Celsius (32°Fahrenheit) and boils at 100°C (212°Fahrenheit). Is there a temperature at which Celsius and Fahrenheit readings are the same?
- What's it Worth? There are lots of different methods to find out what the shapes are worth - how many can you find?
The activities below, taken from the STEM Learning website, complement the NRICH activities above.
Links and Resources
Equations pack one has two relevant sections.
Smile card 1081 (pdf page 12 onwards) has two sets of questions including "think of a number" problems. An example shows how to use the inverse operations in a flow chart method and how this relates to writing and solving a linear equation.
Smile card 0740 (pdf page 21 onwards) encourages students to use a trial and improvement method to solve linear equations. Flow charts are used to show the order of operations in the expressions.
Section B (pdf page 8) contains a section where equations are used to solve problems involving magic squares. Trial and error may be used to solve the problems but an example of a more systematic approach is given.
This video shows a lesson in whcih students write and solve equations. Vocabulary used includes term, expression, variable and equation.
At 11min 20sec a problem involving perimeter of a triangle and square is introduced. A linear equation is written, solved and the solution is checked.
At 20min a problem involving area is introduced which leads to the writing of a quadratic equation and its solution by factorisation.
Simultaneous equations presents a set of ten short problems and solutions of varying degree of difficulty. Most of the problems can be expressed in terms of algebra though some are best solved by intuition. There is a handout showing a set of six "fruit machine" type of puzzles where row totals enable students to find the value of each of the unknowns.