Mystery bag

Mystery Bag is a simple classroom activity. Four bags contain different combinations of coloured tiles. Students draw a sample from each and try to describe the contents. There are a number of cards that describe the possible contents of the bag, and they choose the best one. Watch the Mystery Bag video.


You can also download the Mystery Bag video transcript.


The Mystery Bag: Student Worksheet provides a template for students to record, tally and graph results. You can also download the Mystery Bag: Teacher Notes.

Share class data to provide a larger sample for the basis of discussion about sample variation. Encourage students to compare and contrast their individual results to the class' results so that everyone gains an appreciation of the variations in the smaller samples.

Discuss the features of the tables and how they were designed to suit the data that was collected (i.e. categories for the colours, headings to identify which bag, and spaces for the tally and the totals).

This activity would be appropriate for year 6 students. For years 7 and 8 students, there is a more detailed and open-ended version in the digital object R12165 Mystery bag.

Curriculum links

Year 8: Investigate techniques for collecting data, including census, sampling and observation

Year 8: Explore the practicalities and implications of obtaining data through sampling using a variety of investigative processes

Year 8: Explore the variation of means and proportions of random samples drawn from the same population