8 Summer 2

Reasoning with data


Much of the statistics content in Key Stage 3 is a continuation of that studied at
primary school, and many of the charts and graphs in this half term have been
used in Year 7 and earlier in Year 8. A particular focus is using charts to
compare different distributions. We also explore when graphs may be
misleading, an important real-life consideration. Collection of data is also
covered, including designing and criticising questionnaires.

Students have already met the median and the mean earlier in KS3. This half term
reintroduces the mode and also looks at when and why each average should be
used. Students will also look at the mean from grouped
and ungrouped frequency tables. We also consider outliers, considering what effect
these have on all the measures studied, and whether they should be included or
excluded in our calculations.

Building on

Rounding (Year 7 Autumn 2)

Range & Median (Year 7 Autumn 2)

Bar Charts (Year 7 Spring 1)

Line Graphs (Year 7 Spring 1)

Mean (Year 7 Spring 1)

Scatter Graphs (Year 8 Autumn 2)

Powerful Knowledge

Understand and set up a statistical enquiry
Design and criticise questionnaires
Draw and interpret pictograms, bar charts and vertical line charts
Draw and interpret multiple bar charts
Draw and interpret pie charts
Draw and interpret line graphs
Choose the most appropriate diagram for given set of data
Represent and interpret grouped quantitative data
Find and interpret the range
Compare distributions using charts
Identify misleading graphs
Understand and use the mean, median and mode
Choose the most appropriate average
Find the mean from an ungrouped frequency table
Find the mean from an grouped frequency table
Identify outliers
Compare distributions using averages and the range

Lesson Resources

Lesson 1 – Working with Questionnaires

Lesson 2 – Pictograms

Lesson 3 – Bar charts

Lesson 4 – Line graphs

Lesson 5 – Pie Charts

Lesson 6 – Which statistical diagram is best?

Lesson 7 – Misleading Graphs

Lesson 8 – Working with the range

Lesson 9 – Mean, mode and median

Lesson 10 – Which average should we use?

Lesson 11 – Outliers

Lesson 12 – Averages from frequency tables

Lesson 13 – Averages from grouped frequency tables

Lesson 14 – Comparing data sets