This activity is based on two aspects of the design of bar codes used for products on sale in shops. The first aspect is that of a check digit and how it works; the second aspect is that of the actual design for the strips of numbers that make up bar codes. The activity here only deals with the left-hand side numbers in 8-digit codes but this can be easily extended to 13-digit codes and right-hand code designs.
Number and Measure
Only requires familiarity with digits and basic calculations.
Initial discussion about the significance of bar code technology, not just for shopping but in a variety of contexts; use bar codes that students already have on products; students work in pairs on the check digit tasks and similarly on finding acceptable designs for numbers.
No technology is needed but there is software that can be used for motivation.
The obvious extension is to consider 13-digit bar codes and both right- and left-hand-side codes; other extensions are into different bar codes, designed for other contexts.
This is a resource developed for the Core Maths Support Programme by David Burghes (CIMT, Plymouth University) and Al Reynolds (Exeter School).