What is it?
The mean – and averages in general – is a concept that students first meet at primary school, and yet it continues to crop up and cause problems right up until they do their GCSEs some seven years later. One of the issues I have encountered is that students do not see the mean as a single concept. Rather, they learn a process for calculating it for a set of data, another one for when it is presented in a frequency table, and another when grouped frequency is involved. Rarely are the connections between these three processes connected securely in students’ minds, and thus they are left with 3 rules to remember on top of the 100s of others. Fortunately, this wonderful resource could help. It provides a clear, visual intuitive way to bridge the gap between the mean from a list of data and the mean from a frequency table.
How can it be used?
This Excel spreadsheet is ideal for introducing how to calculate the mean from a frequency table as part of a whole class discussion. The four tabs take us through the four key stages, and each contains a list of great questions that we can ask out students , such as “which new entry will decrease the mean?” and “which will make the mean x?”. Because this is built in Excel, all the calculations have already been done, so have presented students with a question, asked them to reflect and discuss, we can then immediately see the answer. Better still, we can see the answers to any other questions, theories and lines of inquiry they may have. All this is presented in a clear and colourful way that focuses their attention on the things that really matter. I absolutely love this resource.
Thanks so much for sharing