2. Census, Population, Sample

Description of the lesson:

Introduction: Review of types of variables

• Designate the corners of the room as 1. continuous numerical, 2. discrete numerical, 3. categorical, 4. have no idea. Teacher calls out variables and students move to the corner they think is the correct classification. After each variable, ask one student for their reasoning. For the students in the in the 'have no idea' corner, ask scaffolding questions such as "Is this variable represented in words or numbers?". (AFL) (WM: fluency, justification)

This activity revises the material that was learnt yesterday to build their fluency in classifying variables.

Activity: Research activity (LIT/ICT)

• Students research the following questions:
  1. What is a census?
  2. What data is collected in a census?
  3. What is the purpose of a census?
  4. How often is the Australian Census conducted?
• After discussing the answers with the class, ask them why they think the Australian Census is conducted every five years. Why not every year or at least every 3 years with the rotation of government? Answer: logistics takes a lot of resources (time, money, etc.) (WM: problem solving, reasoning)
• Ask students if they know any countries with a population larger than Australia's and ask them to look up how often they conduct their population census.
• Pose a question: If we wanted to know something about the population of Australia, eg. 'How often do Australians visit the beach?', how could we go about finding out? Would we conduct a census? Students 'finger-vote'; hold up 1 finger for Yes or 2 fingers for No. (AFL) Possible questions: Why yes/no? What would be some difficulties in taking a census? What do you think would be a more efficient way of answering our question? Answer: census is impractical so we would have to take a sample. (WM: communicating, reasoning)

Extension: Time permitting, students can navigate through this website http://concensus.splash.abc.net.au/concensus-game/ which visualises the data collected in the 2011 Australian census through in different ways.

This research activity builds students' general ICT capabilities and allows them to discover the practicalities of conducting a census. Students are also able to explore data collected in the 2011 Australian Census through an interactive website.

Activity: Video (LIT/ICT)

• Play the following YouTube clip: https://www.youtube.com/watch?v=eIZD1BFfw8E&t=44s which outlines the difference between population and sample and hand out accompanying worksheet. (WM: reasoning)
• Pause the video at 0:41 to let students predict whether they will find the population. Do this by 'finger-voting'; students hold up 1 finger for Yes and 2 fingers for No.
• After the video clarify any language that may have been confusing for students (Eg. population, subset, reflects, representative)
• Go through answers to the worksheet as a class. (AFL) Students paste the worksheet in their books.

This video introduces students to the difference between population and sample. The worksheet is added to transform this activity from passive learning to active learning, ensuring that attention is paid to the information being presented.

Conclusion: Exit Cards (AFL)