Tag Archives: BIDMAS

300. Name that Number

Simple little starter for you today. Minimum preparation, personalised challenge.


  • Paper or whiteboards


  • Hand out mini whiteboards or use paper.
  • Write the alphabet on the board.
  • Assign each letter a value. You can go for the standard 1 to 26 or choose a mixture of big/small numbers – maybe a negative number or two.
  • Get each student to write down their name and associated numbers.
  • Write a target number eg 100 on your board.
  • Each student must use the numbers of their name to make the target. If they can’t, they must get as close as they can.
  • If they make that target either find another way or change the target number.
  • Alternatively once they’ve finished they could use their classmate’s name – did they use the same method?


  • You can make this as easy or difficult as you want by changing the target or the alphabet numbers.
  • Throw in some fractions or decimals – go all the way and thrown in algebraic indices or standard form. You are the best person to judge your students’ level of challenge..
  • You could allow surnames, you could insist all numbers are used.
  • Put three alphabet variations on the board for mixed ability teaching.
  • If you are teaching a class not in the English language (eg Welsh, Greek, Russian), where the alphabet is different, this still works just assign each letter/character a number in the same way.
  • The possibilities are huge – have fun!

Note: this isn’t numerology, it’s proper Maths!

280. BIDMAS & chips – a second helping

Back in post 231, I discussed using a Fish & Chip shop to introduce BIDMAS. I’ve since taught this topic again and written a resource to go with it:

BIDMAS & chips

There are three different menus – if you hand them out correctly no two pupils should have the same menu. Pupils write their names on the front and fold the menu in half so that they can see the price list.

If you go through the activity in post 231, pupils can use their menus to work out totals without copying from each other. You can then get the pupils to gather into the three different shop groups and argue out the misconceptions.

I used this on my first lesson this year with a shared Year 7 class, in front of five PGCE students and it worked a treat!

231. Fish Shop Maths

I’ve been using this idea since I first started teaching and I’ve finally got around to typing it up!


Image Credit:http://coachandhorsesn16.com/eat/fish-n-chips/

I introduce order of operations by creating an imaginary Chip Shop. I usually read out orders and get the students to write down what they think they are on whiteboards. Note that when you read out the orders, the punctuation doesn’t give any hints.

  • ‘Two fish and three chips’ – 2 fish & 3 portions of chips
  • ‘Fish and chips twice’ – 2 fish & 2 portions of chips or 1 fish & 2 portions of chips
  • ‘Five sausage and chips’ – 5 sausages & 5 portions of chips or 5 sausages & 1 portion of chips

This activity always prompts a ‘discussion’ as to who is correct. The misconception of what an order could mean links nicely with the misconception when working out 2 + 3 x 4. You could also adapt the idea for writing algebraic expressions.

A presentation, with questions, is downloadable in three different formats here:

Fish Shop BIDMAS (pptx)

Fish Shop BIDMAS (ppt)

Fish Shop BIDMAS (ppsx)



186. Fantastical algebra

Have you ever played the parlour game ‘Fantastical Creatures’? Click for a lovely description and example of it by Little Cotton Rabbits.

I’ve adapted this concept for teaching aspects of number and algebra.

Basic arithmetic
Inverse operations
Order of operations
Setting up simple equations
Using brackets with numbers/letters
Solving single sided equations

Strips of paper – one sheet of A4 makes about 6 strips
Coloured pens (optional)

Basic instructions
1. Write an instruction on the top of the strip (portrait orientation). Label it (a).


2. Fold over the strip twice to hide the writing. Write (b).


3. Pass on the strip, do not unfold it.
4. By the ‘(letter label)’, write the next instruction. The letters help you keep track of how many times it has been passed on.
5. Fold over the strip twice and put a label for the next letter of the alphabet.
6. Repeat steps 3 – 5 as required.

The beauty of this activity is that each problem is constructed by a group of pupils and they are in control of the level of difficulty.

Activity 1: Setting up simple equations

Follow the basic activities with the following instructions:
(a) I think of a number and write an instruction
(b) & (c) Now I write an instruction
(d) The answer is write a number

Pupils fold the puzzle up tight and either pass it on one last time or hand them in (to be randomly distributed).

Pupils unfold their mystery puzzle and construct the equation, step by step. My pupils quickly realised the importance of simplifying, but many forgot the importance of using brackets. This was a useful misconception to identify.


Pupils then use inverse operations to calculate the unknown.


The algebraic operations and numerical operations can then be compared.


Activity 2: Problem solving

This follows the same structure as the equation activity, but pupils are describing a geometric problem. In the examples the blue sections are up to the pupils to choose.

Example 1

Example 2


In the second example pupils can visualise the problem as well as using algebraic terms.

Activity 3: Number Skills

This activity can also be used for setting up BIDMAS problems by omitting the algebra.

158. May I take your order, sir?

Imagine getting your class to think about a number topic in a real-life context and subsequently having students leave the lesson feeling happy they could use this skill.

About as real as the square root of minus one? Not if you relate it to breakfast*

Image credit: ifood.tv

I wanted to make estimation more relevant for my class, a low ability Year 10. Outside my classroom I put a breakfast menu and my associate teacher took their orders** as they entered the classroom. I had put mini whiteboards on tables and I instructed the class to work out an estimate and the accurate total for their menu choice(s). The lesson had barely begun and the class were already talking about what they were doing (rather than Halloween antics the night before)!

Once everyone had arrived and settled down, I asked if anyone had underestimated and what this would mean – not enough money and doing the washing up!

I then asked each table how much their group order would cost. Would their overestimates cancel out their underestimates? Would the waiter get a tip? Meanwhile the associate teacher had added up the orders, so we could quickly check their calculations.

What if everyone paid £10? Would you have enough? How much tip would you be leaving? Would it cover a 10% service charge?

We followed up this task with some standard estimating questions.

Image credit: www.fudds.ca

The menus I used for the lesson are from a restaurant chain in California. The useful thing is there are no units of currency, so this works for different countries. It will work equally well with KS2 and KS3 pupils.

Download resource: Breakfast estimation (pdf)

BTW The students decided if the waiter wanted a tip, he should actually feed them first!

*Strongly suggest you use this before students have break or lunch time, or else they’ll be drooling in their next lesson.

**Unless you are providing food, please add the disclaimer that you are not feeding them.