Comparing Value for Money: Baseball Jerseys

Mathematical goals

This lesson unit is intended to help you assess how well students are able to:

  • Interpret a situation and represent the variables mathematically. Select appropriate mathematical methods to use. Explore the effects of systematically varying the constraints.
  • Interpret and evaluate the data generated and identify the break-even point, checking it for confirmation. Communicate their reasoning clearly.


  • Before the lesson students attempt the task individually. After reviewing responses, you formulate questions for students to consider when planning improvements to their work.
  • At the start of the lesson, students think individually about the questions posed.
  • Next, students work in small groups to combine their thinking and work together to produce a collaborative solution to the Baseball Jerseys task, in the form of a poster.
  • In the same small groups, students evaluate and comment on sample responses, identifying the strengths and weaknesses in these responses and comparing them with their own work.
  • In a whole-class discussion students compare and evaluate the strategies they have seen and used.
  • In a follow-up lesson, students reflect for 10 minutes on their work and what they have learned.

Materials required

  • Each individual student will need a copy of the assessment task: Baseball Jerseys, some plain paper, a mini-whiteboard, pen, and eraser, and a copy of the How Did You Work? questionnaire.
  • Each small group of students will need a large sheet of paper, some felt tipped pens, and copies of Sample Responses to Discuss.
  • Provide calculators and graph paper only when requested.
    • There is a projector resource to support whole-class discussions.

Time needed

15 minutes before the lesson, a 70-minute lesson (or split into two shorter ones), and 10 minutes in a follow-up lesson. Timings given are only approximate.