Rich tasks
- These are problem solving open-ended questions that require students to investigate displaying data. The tasks can be given at the start of a topic and done as the students gain enough knowledge to complete them, inserted into a topic at an appropriate place, or given as homework or extension.
- It's a chore
> More on "Rich tasks for this Chapter"...
1. It's a chore
- Students could work in pairs or a group and share out the graphing amongst them.
- Encourage students to draw several graphs for each set of data so they can decide which one would best enable them to answer the questions they have written.
Stem and leaf plots and dot plots
- Draw stem and leaf plots and dot plots from given data.
- Understand that number data can be shown on stem and leaf plots and dot plots.
- Know how to analyse a stem and leaf plot and dot plot.
> More on "Stem and leaf plots and dot plots"...
Teacher notes
- Encourage students to understand that stem and leaf plots can be used to collect data, but the data must be sorted before it can
be displayed. - Dot plots can be used to show categorical data or number data. Because counting the dots can be difficult they are best used when looking for the highest or lowest frequency of data.
Pie charts and strip graphs
- Fill in pie charts and draw strip graphs from given data.
- Understand that pie charts and strip graphs are used to show or compare fractions of data
> More on "Pie charts and strip graphs"...
Teacher notes
- Students need to know that pie charts and strip graphs are used to show fractions (proportions) whilst bar charts, pictographs, dot plots and stem and leaf plots are used to show how many.
- At this level students are only required to fill in and interpret pie charts. They are not required to draw them from scratch.
Displaying data
- Be able to choose an appropriate graph to display categorical and number data.
- Analyse a graph and make statements about what it shows.
> More on "Displaying data"...
Teacher notes
- In level 3 students are expected to work with multi-variate data and time series data, as well as the types of data given in this chapter. Multi-variate and time series data will be covered in book 3B.
- It is important that students get a good grasp of which graphs can be used to show categorical and which to show numerical data.
- Choosing a suitable graph should be related to the purpose of a survey, and the questions asked or assertions to be tested.
- Remind students to give all graphs a title, label the axes and have a suitable scale that goes up in equal intervals on all graphs.
- Encourage students to look for patterns and anything that stands out in a graph.
- Some students find it difficult to find the over all meaning of a graph. They can read off specific values but are not be able to tell you what the overall picture is that the graph is telling you. It is important to practise this. Hint: You could suggest students use highlighters to highlight key information.
- For the misleading graphs question, you could divide the graphs among groups. Each group could share their findings / redrawn graph with another group or two (to closely look at a range of misleading strategies) or with the whole class.
Using graphs to compare data
- Draw graphs to compare data.
> More on "Using graphs to compare data"...
Teacher notes
- When comparing graphs remind students to check that the scales are the same or, if not, then to take this into account
when comparing. - Remind students to look at the title, the labels on the axes and the scale on a graph when reading it. You could make a
checklist of what must be included on a graph. - Encourage students to look for patterns and anything that is different in one of the graphs.
- Encourage students to look for patterns and clusters of data values.
