Te Kete Ipurangi Navigation:

Te Kete Ipurangi

Te Kete Ipurangi user options:

Senior Secondary navigation


Activity: How does your cell phone measure up?

AOs | Indicators | Snapshot | Learning experiences | Cross curricular
Assessment | Spotlight | Links | Connections


Design your own cell phone: create a detailed model.

Achievement objectives

  • GM 6-1 Measure at a level of precision appropriate to the task.
  • GM 6-2 Apply the relationships between units in the metric system, including the units for measuring different attributes and derived measures.
  • GM 6-3 Calculate volumes, including prisms, pyramids, cones, and spheres, using formulae.
  • GM 6-5 Recognise when shapes are similar and use proportional reasoning to find an unknown length.

Links with number and statistics as well depending on how task is progressed.


  • Selects appropriate units for measuring tasks.
  • Identifies limits of accuracy for a measurement.
  • Converts between units.
  • Understands the role of prefixes as conversion factors of base units, for example, kilo means one thousand, milli means one thousandth.
  • Models objects using 3D shapes.
  • Solves problems involving finding volume(s).
  • Uses volume formulae appropriately.
  • Recognises similar shapes using their properties.
  • Uses properties of similar shapes in solving problems.
    • Matching lengths are proportional.

Diagnostic snapshot(s)

See 'research current cell phones'.

Planned learning experiences

Design their own cell phone (physical case not the electronics).

What would you want it to look like, and how big would everything on it be?

Research current cell phones
What are existing cell phones like?

Think about the end point - What do you want the students to get out of this? For example, students have found dimension of screens, keys, arrow buttons, other buttons, dimensions (width, height, depth), weight.
Find information from your manual or phone specification online (or a friend’s or whānau) to look at comparisons across different phones.

Collect the class results.

Possible questions for students to explore

  • Maths models: What shapes best model the different features and the whole phone?
  • What is the ratio of length to width of the phone (link to number strand)?
  • How big are the buttons and are these a standard size? How does hand size affect your use? (Links to number and statistics.)
  • What is the volume of the phone, that is, how much room does it take up in purse/pocket/pencil case? (Modelling – not a perfect cuboid, but can be modeled by – units (choosing) – limits of accuracy (how does the volume change if my measurements are out by _ mm.)
  • Surface area for buying 'skins' (measure the amount of waste if having to cut to size, or make their own 'skin' out of paper for their phone).

Design phone
Use Google Sketchup to create a 3D model.

Design the packaging. Students design packaging for the phone they have designed. (Geometry link)

Students create a short 'promotional' blurb for their design which includes details on the mathematical specifications.

Possible adaptations to the activity

Create models for other common appliances. Design packaging for various cell phones in existence. Design packaging for food and drink.

Cross curricular links


Planned assessment

This teaching and learning activity could lead towards assessment in the following achievement standards.

Spotlight on


  • Encouraging reflective thought and action:
    • Supporting students to explain and articulate their thinking.
    • Encouraging students to fine-tune their mathematical and statistical thinking.
  • Making connections to prior learning and experience:
    • Encouraging students to write stories for mathematical models.
    • Providing real life problems in which the context is relevant to students.

Key competencies

  • Thinking:
    • Students select appropriate methods and strategies when solving problems.
    • Students create models.
    • Students make connections and discern if answers are reasonable.
  • Using language, symbols and texts:
    • Students use symbols and diagrams to solve problems.
    • Students understand and communicate information and ideas using mathematics.


  • Students will be encouraged to value innovation, inquiry, and curiosity, by thinking critically, creatively, and reflectively.


Planning for content and language learning

  • Maintain and make explicit the same learning outcomes for all the learners.
    • How can I make the lesson comprehensible to all students?
    • How can I plan the learning tasks so that all the students are actively involved?
    • Do my students understand the learning outcomes?
  • Begin with context embedded tasks which make the abstract concrete.
    • How can I put these concepts into a concrete context?



  • Lowe, I. (1991). Construction. Mathematics at work - Modelling your world: volume 2 (p. 105). Canberra, ACT: Australian Academy of Science.

Download a Word version of this activity:

Activity: How does you cell phone measure up? (Word, 1 MB)

Last updated September 9, 2018