Stone moving/teacher notes

Moving stones Teacher Instructions

Aim: Investigate how many stones can be moved from one pile to another (15cm apart) in 10 seconds

Objective: Give pupils an opportunity to develop their data handling skills by collecting data and handling it simply.

Essential Equipment:

• Pile of small stones (ideally a similar size, able to be picked up between two fingers and moved easily)
• Stopwatches or clocks, ideally one per group of pupils.

Getting started (data collection)

• The teacher needs explain and ideally demonstrate the task beforehand
• Students probably will need practice with stopclocks

Ideas for class discussion before activity

• How long is 10 seconds? (get the class used to using the stopwatch)
• Ask pupils what they think they can do in 10 seconds. E.g. How many times they could write their names?
• Ask pupils to stand; start your stopwatch; pupils to sit down when they think 10 seconds has passed.
• How might the arrangement of the stones make the experiment fair
• Discuss the need to conduct the experiment in the same way and ask them how they might do it
• Discuss Left-handed or right handed students and how this may make a difference to the results.
• Estimate how many stones they will be able to move in 10 seconds with your dominant hand and with your other hand.
• Discus if they could predict how many stones could be moved in 20 or 30 seconds or longer

The Task

• Place a pile of small stones in a pile, close together but not on top of each other.
• Mark a place 15 cm away in some way (chalk or use a piece of paper)
• Pupils to work in small groups, including one timing, one recording the data and one moving the stones
• Pupils are given a chance to practice moving stones from one pile to another, 15 cm away
• When they are ready, the number of stones that they can move from one pile to the other in 10 seconds is measured. Students use the hand they write with

Analysis of Data

• From the large data set for the whole class students can calculate the mean, mode and median. This could be done using manual calculation, calculators or computer based spreadsheets

Extension activities

• Pupils could repeat the experiment with their non dominant hand
• Pupils could repeat the activity more than once in order to generate an individual average

Further options for data analysis using spreadsheet program

• Pupils can enter their own data individually into the computer spreadsheet or one member of the class could record all class data
• As well as the calculation of mean, mode and median, the spreadsheet program could be used to draw histograms of the class data
• Discussion about which value to enter for the group could involve looking at the highest, middle or lowest value. Obviously, class agreement to standardise this is essential to make comparisons fair.
• Demonstrate how the graph is created using the software and discuss the range for the class.