Preview · the opening missionRead this to the class:
A TV weather forecaster is new to the job. Her notes say: "At 7:30 a.m. it was −20 °C. Two minutes later it was 7 °C." She wrote the change as 7 − 20 = −13, and was about to tell viewers it got 13 degrees colder. Her producer stopped her: "That can't be right. It got warmer!" Your team's job: work out how temperatures really change when they cross zero, and fix the forecaster's maths before she goes on air.
Teams of three, with jobs that rotate every round: Roller (rolls the dice), Counter Keeper (models the move with counters), Recorder (writes the equation and marks the thermometer).
Look inside the PDF
Sample pages, stamped “preview”. The download is the clean, full lesson.
In the full lesson PDF
8 printable pages
- Predict (5–10 min)
- Hunt (20 min)
- Reveal (10–15 min)
- Act (10 min)
- Background for the teacher
- Assessment
- Student sheet
- Worksheet: Label it
- Worksheet: Try it at home
On the student sheet
- My prediction
- Temperature-swing game
- Thermometer
- What did we find?
- The corrected script
- Exit ticket
- Label it
- Try it at home
US Letter, prints cleanly in black and white. The student sheet is on its own page, ready to photocopy.
Free with an account (any 3 lessons), or US$19 for all 4 lessons in this unit.
What students show by the end
- Adds integers
- Subtracts integers
- Explains zero pairs
From the lesson’s rubric, which scores each one as not yet, getting there or got it.
Questions teachers ask
How long does “How much did the temperature change?” take?
50–60 min. Group size: teams of 3.
How much prep does it need?
10 minutes: each team needs 20 counters of one colour (positive, for example yellow) and 20 of another (negative, for example red), or paper squares cut in two colours, plus two dice of different colours. Print the Student sheet with its thermometer from −20 to +20.
What materials do I need?
Two-colour counters, or paper squares in two colours; dice in two different colours. Cost: free with counters and dice; or cut paper squares in two colours.
Which curriculum standards does it cover?
Common Core Math (US): 7.NS.A.1 and 7.NS.A.3 (partly).
What’s in the lesson PDF?
A teacher guide that walks you through predict, hunt, reveal, act, background for the teacher and assessment, then a student sheet (“My prediction”, “Temperature-swing game”, “Thermometer”, “What did we find?”, “The corrected script”, “Exit ticket”, “Label it” and “Try it at home”) on its own page, ready to photocopy. It’s US Letter and prints cleanly in black and white.
Can I try it for free?
Yes. A free account includes any 3 full lessons of your choice, and this can be one of them. After that, this unit is US$19 for all 4 lessons, yours to keep, or every lesson is US$199 a year.