Thomas G. Edwards, Aslı Özgün-Koca & John Barr (2017) Interpretations of Boxplots: Helping Middle School Students to Think Outside the Box, Journal of Statistics Education,25:1, 21-28, DOI: 10.1080/10691898.2017.1288556
Big guiding question:
What’s the best way to teach box plots?
Going from data to box plot is easy. Going from box plot to data/analysis… not so much.
How to 6th/8th graders interpret box plots and how can we intervene to improve their interpretation?
Student observation. n=132+127. 50 min, one paper/pencil task, one TI Inspire task
Kids can make a box plot, but don’t understand that they’re doing or what the box plot means, basically. Results in line with lit review.
Teaching suggestions in table 1, and
Students don’t get percents? They aint gunna get box plots.
Don’t rely on naive intuition, it fails with box plots
Just because they can make a box plot doesn’t mean they can read one.
Delay box plots until 7/8 grade.
Did they answer their research question?
Sort of. They found interventions, but didn’t find out if those interventions actually work.
Possible application to curriculum
Fluency converting between fractions and percents
Fluency finding 25%, 50%, 75% of a whole
Activity highlighting inverse proportionality of length of box/whisker and density.
Questions to ask kids
“why is upper quartile box narrower than lower quartile box?”
“why is left whisker longer than right whisker?”
Compare/contrast different representations of same data set