Using data with confidence

Welcome to Using data with confidence, a suite of resources that will assist you to read, understand and interpret data. 

For information about the face-to-face course for NSW public school staff, visit the CESE website

Downloadable calculator and workbook

To get the most out of this online resource, download:

The Educator Calculator - TEC (ZIP, 714kB)

Using Data With Confidence Excel Workbook (XLS, 32kB)

This resource is also available as printable manual (PDF, 2.3MB)

TEC is a multipurpose calculator comprising of 7 tabs – TEC 1 to TEC 6 and Boxplots. Simply enter all the marks from tests or assessments into the TEC tabs and they will automatically calculate:

  • number of values / sum of values
  • the mean, median and modes
  • minimum and maximum
  • variance
  • standard deviation
  • confidence interval amount and scale
  • quartiles and interquartile range
  • percentiles
  • boxplots


Example of a TEC tab


The Boxplot tab displays all boxplots, enabling you to compare up to six sets of marks.

 Example of comparison boxplots


The Excel Workbook contains 9 tabs. Each tab corresponds with units in this online resource, and is where you enter Excel formulas.

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