## An unusual way to teach plotting straight line graphs…

Image via Wikipedia

I bet you’ve not seen this one before…

There is a linear relationship between air temperature and the number of times a cricket ‘chirps’ per minute. What an interesting idea for a lesson on plotting straight line graphs!

After putting across the idea of the relationship, and motivating the pupils by explaining how the next time they are out and about in the countryside and want to know what the temperature is they can work it out by listening to crickets, give them this worksheet which gets them plotting the linear relationship between degrees fahrenheit and chirps per minute. The worksheet is quite scaffolded and I took some artistic (mathematician’s) license to adjust the coefficients of the equation so that it was more appropriate for secondary school pupils to work with. After working out their table of values and plotting the straight line graph they are given questions that assess their ability to interpret the graph.

If degrees Fahrenheit means nothing to you (because like me, you are English) then you can move the lesson on by giving the pupils this worksheet that gets them plotting the degrees Fahrenheit to degrees Celcius temperature conversion chart. Note the slight increase in pitch with the decimal number coefficient and the negative axes. There are some more interpretation questions to follow once they have completed plotting the graph.

A really nice plenary to this lesson is to get a pupil up at the front and get them to do cricket chirping noises with the rest of the class counting how many they made in a minute. The class then have to use the graphs they have plotted to work out the ‘temperature’ in both degrees Fahrenheit and Celcius.

Great fun and a bit different than teaching this topic from a dry textbook…

## Teaching the properties of equality through problem solving- repost from Keeping Mathematics Simple

Image via Wikipedia

I’ve found getting some pupils to understand the concept of equality to be surprisingly difficult. The problem seems to limit pupils’ ability in many other topics such as equivalent fractions, solving equations and changing the subject of a formula. I stumbled upon an article the other day that gave me some insight into why pupils struggle with it. When you do a calculation on a calculator, what button do you press to get the answer? The equals button. The article argued that kids think of the equals sign as an operator. Kids see the equals sign as something you press to get an answer.

Enlightened with this possible explanation for kids’ misconceptions, by fortune I then came across an interesting blog post by the excellent Keeping Mathematics Simple blog called “How to teach the properties of equality through problems solving“. The author puts forward a way of teaching the topic of solving linear equations. Her method, of focussing on developing the concept of equality first, before moving on to solving the equations later is logical and well thought through, ensuring there is no misconception about the properties of equality before teaching how to solve the equations.

When teaching solving linear equations (or similar) in the future I think I’ll experiment first with giving them something like 2x = 10 and ask them to come up with 5 equations based manipulating the first one (do the same to both sides etc…) e.g. 4x = 20, 2x + 2 = 12 and so on. They could produce a spider diagram with the starting equation in the middle and alternatives off on legs. Once they solve for x they can then subsitute it back into all of their equations and they’ll see that the statements of equality still hold true. Hopefully this will help develop an understanding of the properties of equality which is so important if their learning of solving equations is going to be anything less than procedural.

## 4 great resources for teaching collecting like terms in algebra

Ever been teaching collecting like terms (simplifying) and just needed 20 questions you could put up on your interactive white board to set the pupils off on? Looking for the questions to be differentiated according to ability and for the answers to be on the next slide? If so, check out this pdf slideshow!

Instead of a list of questions, how about giving the pupils a ‘collecting like terms pyramid’ to climb! The worksheets work in the conventional manner where the bricks above are made by collecting the like terms from the two below. The worksheets are differentiated as easy and a bit harder.

Alternatively, just looking for a conventional worksheet, but one that has lots of scaffolding with worked examples and an explanation of the process? If so then check out this worksheet!

Hope you find these resources handy!

## Probably the best blogs by maths teachers around the world

Image by DavidErickson via Flickr

There are some really great blogs out there written by maths teachers who really care about their practice. I enjoy reading their posts as they share their insight and ideas and think about how it could improve my own teaching.

There is wheat and there is chaff out there. To save you time in separating the two, I have compiled this list of the best blogs I have found so far: Read more of this post

## Pure inspiration- nature by numbers

This has to be one of the very best videos I have ever seen to show the beauty and power of maths. Just imagine all the ways you could use this to inspire the kids.

## Taboo words

Thanks to Sarah for this brilliant way to assess understanding of concepts and maths vocabulary.

Split the class up into groups of 4-6. Each group gets a set of small cards which each have on them one maths related word. The first thing they have to do is write on each card, under the math related word which is at the top, three words that people will not be allowed to use when describing the top word. For example, if the top word is circumference then three words the team could write underneath could be circle, perimeter and length. The idea is to make the describing of the top word as tricky as possible. The words that they can’t use when describing the top words are called Taboo words.

The sets of cards are then passed onto another group and one person in the group gets 1 minute to describe as many of the top words as possible to their group colleagues without using the taboo words. The teams get a point for each correct word they guess. Each team has a go and the scores added up at the end to identify the winning team. You can do a tie-breaker round if necessary.

There are lots of variations you could do of this game and it does seem to really engage the kids and is an excellent way to revise key vocabulary and assess conceptual knowledge.

## Introducing algebra- consecutive numbers addition puzzle

Here’s are really good way of introducing algebra and getting across the idea of what a variable is. The pdf slides that you can use on the interactive white board to run this activity are here.

Start by getting the pupils to draw this diagram in their books:

## Mexican Wave Sequences

A great little game to make sequences fun!

Get the pupils into a horseshoe. Put up an nth term rule on the board. They have to do a mexican wave around the horseshoe but as they stand up they have to shout out the next term in the sequence. The first person is n=1, second person is n=2 etc… See if they can get all the way around the horseshoe without making a mistake. If they do make a mistake they have to start again! Increase the complexity of the nth term rules as you go along!

A great game as it reinforces the idea that the common difference is the coefficient of the n term.

Sorry, I can’t remember who put forward this idea but it is brilliant. Thank you!

## Substitution Top Trumps

﻿Do you remember playing the Top Trumps card game as a kid? Here are a couple of Top Trumps card game resources that will make any lesson about substitution really fun.

Click here for the dinosaur substitution Top Trump cards. These are for higher attaining classes and feature brackets and indices.

There are lots of ways you can play Top Trumps but here’s one suggestion of how you can run the activity:

• Give one set of the cards to each pair.
• Place one of the cards defining a=, b=, c= on each table.
• Each pair splits their set of cards randomly into two and take one pile each.
• The first player speaks out a characteristic and the value (obtained by using substitution), e.g. “Speed 5”.
• The second player would look up the speed characteristic on their card and calculates the value.
• The person with the highest value is the winner and takes both cards and puts them at the back of their pile. If it is a draw then each player puts their own card to the back or their pile.
• The winner then starts the next turn by looking at the next card in their pile and reading out a characteristic and the value.
• The game carries on until one person has all of the cards.

Have fun!

Thanks to “kez84” on www.tes.co.uk for this excellent resource and also to Steph W for suggesting it.