Grade 6: Statistical Investigations

Warm up with a quick recall on the board. Work the whole cycle: pose a question, collect the data into a table, choose a display, then interpret it (total, mode, range, differences) and report what it shows.

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. Model the method clearly, thinking aloud:

• Start with a specific, answerable question (how do students in our class travel to school?), not a vague one.
• Plan the collection: who to ask, how many, and how to record it fairly so the sample is not biased.
• Choose a display that suits the data type: a bar or picture graph for categories, and summarise with a suitable average.
• Interpret the graph and the average to answer the original question, rather than just describing the numbers.
• 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.

Do the first few questions of the practice worksheet together, one child explaining each step. Check for understanding before releasing the class to work alone.

Students complete the worksheet independently. Hand out the three difficulty levels below so every child works at the right stretch.

Circulate and look for these, they are the usual sticking points:

• 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.
• Collecting data before the question is clear, and confusing the range (spread) with the total.

Pull the class back together. Ask one child to explain statistical investigations in their own words, pose a single check question everyone answers on a mini whiteboard, and name what you will build on next lesson.

Use the independent worksheet as the evidence. A child who can complete it accurately and explain one answer has met the objective; anyone who cannot needs the easier level and a short reteach next session.