Stem and Leaf Diagrams
statistics 14-16 GCSE stem leaf

Description/Aim





Statisitics provide powerful indicators, if used wisely, to gather evidence about complex issues. Are the children of single mothers more likely to end up with lower incomes, in borstals (youth prisons)? Are high earners less likely to smoke than low earners due to greater education and hence awareness of the health risks? Controversial subjects that without a body of evidence to provide some clarity can result in painful prejudices and inaccurate assumptions. Definitive answers are difficult with such complex issues. Probabilistic likelihoods provide perhaps, a more representative and useful tool?
Teachers Notes - Why? How? What?

Why we like this activity ….

The statistics are up-to-date (Olympics 2008). We feel that a lot of textbook questions students cannot relate to because the information is so quickly out of date. Here we provide you with some up-to-date statistics, but more importantly, websites to visit that will permit you to keep them continually up to date and relevant to your students:

http://www.iaaf.org/statistics/toplists/inout=O/age=N/season=0/sex=M/all=y/legal=A/disc=100/detail.htmx

Many young people dream of being sports stars. This provides a weblink and real information on what that might take! This engaging with student desires hopefully provides a "hook" to ensure student motivation.

How this activity be used ….

The images can be cut & pasted into whatever presentation software your mathematics department uses: promethean, smartboards, powerpoint, easiteach etc. so that you can construct a "sprinters heights" stem&leaf with the students. Students use the worksheet to keep good notes and all their work in one place. Their aren't hundreds of questions the same, but only a few, which will allow students to make some real and surprising, or at least interesting, conclusions as to physiognomical differences between aspiring endurance runners & sprinters heights & weights. A real context helps to clarify how we interpret interquartile ranges, medians e.g. the upper quaritle shows us that 25% sprinters are taller than the tallest endurance runner!

What to expect when using this activity – from our experience

The success of the activity is to an extent determinant on how well you manage to communicate to students how this analysis can help them understand something about the selection procedures used in modern sport. Use youtube to show some clips of sprinters and endurance runners at the Olympics or something about the Australian Institute:

http://www.youtube.com/watch?v=dH0XWM5TRE8

http://www.youtube.com/watch?v=LyKOy51mTpM

Or budding young athletes talking about their dreams of one day making it big. Get your class talking about sports they enjoy etc. Get them personally investing in finding out the results of the analysis or how they could use these skills to help them in their lives.

 

Extra Notes