Designing the Classroom Curriculum Designing the Classroom Curriculum | Page 146

Designing the Classroom Curriculum
of moderation (i.e. teachers meeting to review work samples and thus agree standards) means such ‘analysis’
will be consistent and valid within a school/ cohort or education system. The process of collaborating to
review assessment is a powerful mechanism for teaching improvement. A Cohort Identification Table can
provide helpful in examining such data.
Table 11.4: Statistical Calculations
Statistic Formulae
Calculating
‘means’
averages. Mean = Sum of all scores / number of scores
or
Calculating the
‘range’ of scores Range = highest score – lowest score The range determines the spread of scores—how far
apart the highest and lowest score is. A small range
indicates similar or like abilities / achievement, however
a wide range indicates many differing abilities/
achievements in a class with respect to what has been
assessed.
Calculating
‘Standard
Deviation’ See:
http://www.robertniles.com/stats/stdev.shtml The standard deviation (SD) enables the teacher to ‘see’
how tightly clustered scores are around the mean. 67 This
calculation is useful when comparing test scores from
different cohorts or schools. In simple terms a small SD
indicates that scores are close around the average while a
large SD indicates their diversity. For example School X
and Y may have the same average in mathematics, but by
applying a SD calculation, one comes to realise that most
students in School X achieve around the average,
indicating very similar abilities, while School Y has scores
ranging from very low to very high indicating extremities
in abilities. The teaching strategies will need to be
different in each case.
Effect size is a simple way of quantifying the difference
between two groups that has many advantages over the
use of tests of statistical significance alone. Effect
size emphasises the size of the difference rather than
confounding this with sample size. In simple terms
teachers can ascertain how much effect (progress) a
classroom curriculum has had on students by comparing
two sets of data (before and after).
For a detailed set of steps
Calculating
Effect Size
See (Effect size calculator)
http://www.uccs.edu/~lbecker/
See also Hattie (2009) for education use of
effect sizes.
67
Benefits to Teachers
The mean (or average) enables the teacher to ‘see’ the
middle score and thus creates a ‘benchmark’ for score
comparison: i.e.: at, above and below the average or
‘middle student’. A high average represents high overall
class achievement while a low would represent the
opposite.
Sourced from http://www.robertniles.com/stats/stdev.shtml
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