hold your breath

various statistical surveys suggest that children can hold their breath for up to and slightly beyond a minute

that makes it a good experiment for a classroom task on representing data

have a large clock (digital display preferably) available
ask students to take a deep breath, hold their nose and hold their breath for as long as they can
after one exhalation at the end, they note their time on a small wipe-board

at one school they get students to come out with their boards and get into groups according to the decade numbers (in seconds)

they then arrange themselves - so that an ordered stem and leaf plot is produced physically


as an alternative to breath holding, students could work in groups to see how long they can stand on one leg when they are blindfolded (or have their eyes shut - the 'blind stork' test)

again a minute is usually the most that people manage

they could compare standing on their right and left legs, possibly producing a scatter graph or a back-to-back stem and leaf diagram from the two data sets