How to teach statistical investigations

Grade 5 to Grade 6

A statistical investigation is the whole cycle of answering a question with data: pose a clear question, plan and collect the data, display and summarise it, then interpret the results and report back honestly about the limits. It pulls together averages, graphs and data critique into one process.

How to teach it

1. Start with a specific, answerable question (how do students in our class travel to school?), not a vague one.
2. Plan the collection: who to ask, how many, and how to record it fairly so the sample is not biased.
3. Choose a display that suits the data type: a bar or picture graph for categories, and summarise with a suitable average.
4. Interpret the graph and the average to answer the original question, rather than just describing the numbers.
5. Report honestly: state how many were surveyed and what the results can and cannot claim, since a small class sample does not speak for everyone.

Common mistakes

• Asking a vague or leading question that the data cannot answer.
• Collecting a small or biased sample and then over-claiming from it.
• Choosing a display or an average that does not suit the data.
• Describing the graph without answering the question that was posed.