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Balancing act 1
Set the question:
How long can typical year X students balance on one foot with their eyes closed?
Data collection
Negotiate rules for collecting data:
- wiggle but not hop
- some part of foot always touches floor
- rules for starting
- timing, finishing
- which foot.
Discuss how many measurements would be needed for a good estimate.
In groups of three (alternating as balancer, judge, timer) carry out the measurements and record.
Representing data
List and order data for each group and then for the class.
Create a stacked dot plot for class data.
Summarising data
Discuss mean, median, mode, range, outliers and clumps in the data.
Create a box-and-whisker plot (if appropriate for year level).
Degree of certainty
What aspects of the investigation affect the variation in the data and the uncertainty of the conclusion?
Would the data look the same if another class collected their data?
Drawing an informal inference
Write a report, including all of the assumptions made and limitations experienced, to explain how the class arrived at how long typical year X students can stand on one foot.
