Averaging results, sorting results and carrying out calculations.

I’ve used Excel when calculating the speed of students to work out their average speeds and then rank them in order.  In the spreadsheet below I am averaging the reaction times of students.  If you’ve tried getting SEN students to do this with calculators you’ll know what a life saver a spreadsheet can be.

Graphing results

I have excellent graphing software for simple graphs, and I recommend 2Simple’s software for standalone graphing that students of low ability can use independently.  There are occasions however when you need something a little more powerful or flexible, or when you want to embed a graph along side results tables etc.

This graph from an excel sheet has a trend line to help students see a relationship

This graph shows an average of reaction times.  Data entry can be fiddly, but we had numerous errors when students had to convert their times into seconds to average themselves (and I provided extra data to average with the pupils’ own data of varying quality so they always saw the trend I wanted).

Conditional formatting and the IF command

Conditional formatting can be extremely useful to help learners interpret their results.  Results can be colour coded (and errors from averaging empty columns can be hidden). 

In the spreadsheet above the average box changes colour to help pupils interpret the results (red = worse, green = better) using conditional formatting (after comparing the two averages).  The better or worse statements are completed automatically based on the averages calculated as pupils enter their results (using an IF statement).   Cells with errors are formatted (conditional formatting again) to appear as white text on a white box.

I hope these examples have given you an idea of some of the ways that spreadsheets can be used in a science lesson.  Don’t worry it you don’t have access to a suite of computers, many of these activities work just as well with a single spreadsheet hooked up to an interactive whiteboard (IWB).

I took some KS3 APP data (you can’t see it all here) and calculated the average in different ways.  As you can see the method of calculating an average can make a whole level of difference.  The longer the time you are measuring over, the more significant the difference is.

My preferred method is to average the five highest marks.  I aim to collect around 10 pieces of APP data over a year from a variety of activities.  You would expect pupils to make progress over a period of time, with the amount of progress proportional to the time span you measure over.  Are you doing pupils any favours if you take a simple mean average?

I’m not convinced that my method is best, but it allows students to have a few ‘off’ days without bringing down their average.  What method (and over what span of time) do you calculate an average?  What method works best for you and why?