In this unit, students learn what vital statistics are, and that Statistics New Zealand collects and collates these data. The focus is for students to present and communicate a chosen aspect of population statistics in the most appropriate graphic way, and to explain and justify their choice of visual display.
- Display collected data in an appropriate format.
- Produce bar charts of data using Microsoft Excel.
- Plan a statistical investigation.
- Make statements about implications or possible events based on selected data.
The focus of level 3 investigations typically expands from students exploring information about themselves and their immediate world, to exploring information in, and about, the wider world.
Accordingly, in this unit, students develop an understanding of vital statistics (quantitative data concerning the population, such as the number of births, marriages, and deaths), of where these can be located, of how useful and interesting they can be, and how best to represent these data visually.
As students are exposed to a range of population data they should select data of particular interest to them, and consider and choose the visual data display that would best present the numeric information.
Within this, students will apply their knowledge and experiences, developed during Level 2, of frequency tables, bar graphs, strip graphs, and pie charts for category data; dot plots and stem and leaf graphs for whole-number data; and simple line graphs for time series data.
Students should use computer technology to create these displays, to find patterns, to communicate their findings to others, and to justify choice of display/s.
Background
The Department of Internal Affairs registers births, deaths and marriages (BDM) and maintains NZ birth, death, marriage, civil union and name change information, and issues certificates and printouts.
The registration number is a unique number allocated to every registered birth, death, marriage or civil union,
Information on the number of births and deaths registered in New Zealand is published once a year: https://www.stats.govt.nz/topics/births-and-deaths
Statistics on the number of marriages, civil unions, and divorces registered in New Zealand is also released annually: https://www.stats.govt.nz/topics/marriages-civil-unions-and-divorces
The learning opportunities in this unit can be differentiated by providing or removing support to students, or by varying the task requirements. Ways to support students include:
- grouping and pairing students strategically to encourage tuakana-teina (peer learning) and productive learning conversations
- providing explicit and direct teaching and modelling around how to find percentages of whole numbers
- specifically choosing one or more types of data displays to introduce in session 2, and providing relevant teaching and scaffolding
- providing scaffolding and teaching around each step of a statistical investigation. See Planning a statistical investigation (Level 3) for further teaching ideas around statistical investigations.
The activities in this unit can be easily adapted to draw on the interests and experiences of your students. Instead of investigating name data for their own birth year, and for that of a parent or grandparent, students could investigate name data for the birth year of a favourite sports person or historical figure that they are currently learning about. Consider how this context might relate to your students' interests, cultural backgrounds, and their learning from other curriculum areas.
Te reo Māori kupu such as ōrau (percent) and tūhuratanga tauanga (statistical investigation) could be introduced in this unit and used throughout other mathematical learning.
- Access to the internet
- Graphing materials (either Excel or similar or graph paper etc.)
Session 1
As a class:
- Ask students if they know what the population of Aotearoa New Zealand is.
Look online for an estimate of the current population. Discuss whether the number you find online is exact.
What might change the number? (births, deaths, people entering or leaving the country) - Ask what they think the letters BDM stand for (births, deaths, marriages) and what vital means (absolutely necessary; essential).
Have students explain to each other what vital statistics are, and suggest where data for NZ might be found. - Together visit, explore and discuss: https://www.stats.govt.nz/topics/births-and-deaths
Ask how these data/statistics are gathered. (You are legally required to register BDM).
Make clear that this information is collected as it occurs, unlike census of population and dwelling which is carried out every 5 years information in NZ. - Together, visit, explore, and discuss the Department of Internal Affairs site: https://www.govt.nz/organisations/births-deaths-and-marriages/
- Discuss the services that BDM provides and point out that family history can be explored using this database.
- Brainstorm the kind of information that might be collected in a census: (population and dwellings, age and sex, cultural diversity, relationship status, qualifications, work, income, families, households, phone, internet, transport, housing, business) and the types of questions that might be asked.
Session 2
Have students work in pairs with online access:
- Access and explore NZ census cultural diversity statistics: https://www.stats.govt.nz/reports/2013-census-quickstats-about-culture-and-identity
Have students look at the way in which the numeric data are presented on the tables (some include category totals with percentages, and others present changes to the totals of variables that have change over (3) years).
Discuss percentages and, as appropriate, review how to calculate percentages on a calculator. - Have each student identify a data set which is of particular interest to them. List types of possible data displays and have students discuss with their partner the best display to use for their chosen data set.
- Each student should plan and create a graph which best displays their chosen data set. They should write accompanying statements about the data, make inferences or predictions if appropriate, and record the reasons they chose the particular display. You may need to teach students how to create a specific type of data display, limit the data displays students can select from, or provide modelling to small groups of students around the creation of data displays and the writing of accompanying statements.
- Have students present and share their work. They should read and critique each other’s displays and, where an incorrect choice is made, suggest a more appropriate format.
Session 3
Individually or in pairs:
- Access and explore the first name spreadsheet:
http://www.dia.govt.nz/diawebsite.nsf/wpg_URL/Services-Births-Deaths-and-Marriages-Most-Popular-Male-and-Female-First-Names
Ask students if these data are vital statistics.(No, these data do not show numbers of BDM)
Have students locate data for their own birth year, and for that of a parent or grandparent if they know this. - Have students suggest an investigation they could undertake: For example.
How many students in the class/school share the same birth year as the investigating student?
What fraction or percentage of these names are in the top 10% (20% or 50%) of the most popular names recorded in NZ for that birth year?
What fraction or percentage of student names are not listed at all in the data list for that year. Why might that be? - Students plan their investigation in pairs. If appropriate, frame the context for these investigations in relation to learning from another curriculum area.
- Discuss students' plans for their investigations. (It is likely that one well planned and coordinated survey or data gathering exercise will serve to gather the data to answer all questions.)
- Have them carry out their investigation and share their findings.
- Reflect on the name data that can be generated from the compulsory registration of births. Have students suggest other data that may be of interest.
Dear Parents and Whānau,
This week in maths we are reading statistical data about New Zealand’s population.
Ask your child what are some of the interesting facts they have learned. You might like to investigate together the data available here, including finding out if your name was in the list of most popular names for your birth year.