2. Year 7 Calculator Challenge Lesson

3. Getting to know your calculator
Look at your calculator
What is the difference between the scientific calculator and the ones you have used before?
How can each key have more than one function?

4. How will you deal with the brackets on your calculator?
Brackets-a-go-go
How many different ways can you use brackets to create different values for this expression?
7 x ÷ 2 – 1
How would you use brackets to give these values?
How will you deal with the brackets on your calculator?
= 31
= 35
= 84
= 49
= 41
= 17
Are there any more values that the calculation can have?

5. Multiple Digit Magic 444 4 + 4 + 4 = 12 444 ÷ 12 = ?
Write a 3-digit number where all the digits are the same. Add up the digits. Divide the 3-digit number by the sum of the digits. Record the quotient (answer). Repeat with other numbers. What do you notice? Why do you think this happens?
444
= 12
444 ÷ 12 = ?
I noticed that ….
I think this happens because …

6. Multiple Digit Magic
What if we think of the number as nnn? Can we use place value to think about the number? How can thinking about this help us to explain what is happening? Can we enter nnn into the calculator???
I noticed that ….
I think this happens because …

7. Be Square!
Which numbers can be expressed as the sum of two squares? 5 = = Which of these numbers can also be expressed as the sum of 2 squares? 14 25 6 26
122 40
153 21 56
102 53 77
123
164 72 35 99 65 64 5 51 43
104 55 29
130 27 16
148
125 34 22
140 20 36 19 13
100 90 9 49 73
160 82
109 17 50
103

8. Rooting it Out!
How accurately can you estimate the square roots of numbers?
What strategies can you use to estimate the square root of a number?
What maths do you think the key is doing?

9. Beyond Integers: Call that a number?
Is the following statement always, sometimes or never true? Explain your reasoning. ‘Addition and multiplication make numbers bigger, subtraction and division make numbers smaller.’
What count as ‘numbers’?
What do we mean by ‘bigger’ and ‘smaller’?
How do we describe the different values in an expression or calculation?

10. Beyond Integers: The key keys
Is the following statement always, sometimes or never true? Explain your reasoning. ‘Addition and multiplication make numbers bigger, subtraction and division make numbers smaller.’
Pressing this key before entering a value will make the value negative
This key will allow you to enter fractions into the calculator
Shift and this key will allow you to enter mixed numbers
Use the arrow keys to move the cursor to the correct part of the fraction or mixed number
This key (toggle key) allows you to switch between fraction and decimal answers

11. Beyond Integers: Call that a number?
‘Addition and multiplication make numbers bigger, subtraction and division make numbers smaller.’
I think the statement is always/sometimes/never true because …
Here is the evidence to support my answer:
Use the language in the table to complete the sentence in as may ways as you can
If the numbers being
are
then the
will always be
added
multiplied
subtracted
divided
whole numbers
greater than 1
less than 1
fractions
decimals
mixed numbers
sum
product
difference
quotient
resulting value
result
greater than the initial number
smaller than the initial number
smaller than 1
greater than the dividend
smaller than the multiplicand

12. Beyond Integers: Call that a number?
Is the following statement always, sometimes or never true? Explain your reasoning. ‘Addition and multiplication make numbers bigger, subtraction and division make numbers smaller.’
I think the statement is always/sometimes/never true because …
Here is the evidence to support my answer:

13. I think ….
When you are working with a friend, use these to explain what you are thinking …
It could be this because …
It can’t be this because …
If we do this then …
I wonder what will happen if …
I know this so …
It’s an even number …
It’s bigger than …
… if we multiply by 10 then …
It’s smaller than …
… the answer has to be …
It’s an odd number …

14. About MEI
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Independent UK curriculum development body
We offer continuing professional development courses, provide specialist tuition for students and work with employers to enhance mathematical skills in the workplace
We also pioneer the development of innovative teaching and learning resources