The Number line tool has been developed as an easytouse resource in which you and your students can quickly explore a range of statistical calculations and graphs from small scale data sets.
It is not intended to handle large data sets for which other ICT resources are more appropriate.
The environment will support a range of thinking skills which underpin rich mathematical activities and will help students to:
 Understand mathematical notation
 for example, how the fractions 17/20 and 0.85 are related to each other
 Develop a need for mathematical conventions
 for example, why we have to make a decision about what to do with the digit 4 in 23.45 if we round the number to one decimal place
 Make and test conjectures
 for example, predict where on the Number line a will be less than n if they are related by the equation a = n X 2
 Develop a fascination with our number system
 Explore independently the relationships within and between numbers
Entering a set of data Number line
When you launch the tool, you will be prompted to define your Number line by entering a minimum and maximum value. Twenty numbers will always appear on the line. You define the number of marks between each number by entering a value in scale marks.
At this stage you will want to consider the most appropriate numbers for your students and whether you are working within the range of positive and/or negative numbers or both and whether you require decimal or fractional representation.
Entering these numbers: 

Would give the following Number line: 

Whereas, choosing 

Would give this Number line. 

If you select to display fractions (by clicking on the Show button next to Fractions), these will appear beneath the Number line. (You can also choose to hide the decimal Number line and only display the fractions.)


You can reveal the decimal value of n by selecting on


It will be displayed to the number of decimal places chosen when the Number line was created.
With your Number line created, if you now click and drag the point ‘n’ it will move freely along the Number line.


Using a second point to introduce variables
It is very straightforward to be able to position a second point, say a, on the Number line that is related to the movable point n.
Begin with a simple Number line with integer values, no scalemarks and an accuracy of one decimal place. Hide the value of n.
To introduce another point on the line that is dependant on the value of n, select Options and switch on one of the points (a, b or c).


You will then be able to edit the point. The calculator screen shows the rule a = n – 2 being defined.


When you select ok on the calculator screen and close the Options window, the second point will be displayed on the Number line.


Be aware that the new point may not be visible on the Number line if its value is outside of the range of numbers! You will need to drag n to try to find it! Take advantage of this feature by encouraging students to “troubleshoot” where the point has gone!
Only the point n can be dragged – you can ask students to consider why this might be the case? (a is the dependent variable and is “driven” by the point n).
The values on n and a can be revealed and hidden, as required.

There are a range of functions supported by the Number line which are:
Calculator Key 
Definition 
Example

neg

negation

a = neg n would mean a = n

^

exponentiation “to the power of”

a = (n2)^2

sqrt

square root

a = sqrt(n) would return the positive square root for positive values on n.

sin cos tan

trigonometric functions
sin
cosine
tangent

a = sin(n)
If the calculator is in Degrees, very little movement will be seen on the Number line. To explore trigonometric functions in more detail, switch to Radians.

round

Rounds a function to the nearest integer.

a = round(n)

abs

absolute
Finds the “magnitude” of the function.

a = abs(n)

log

logarithm to base 10

a = log(n)

