Preview · the opening missionRead this to the class:
A geography quiz show asked: "Which is further from sea level: the top of Mount Everest or the bottom of the deepest ocean?" Contestant A said, "Everest, because 8,849 is a positive number, and the ocean depth is negative, so it's less." Contestant B said, "The ocean, because it's further away from zero." The judges can't agree. Your team's job: build a number line of the real world, place every card on it, and decide which contestant should win the point.
Teams of three, with jobs that rotate after each card: Calculator (works out where the card goes), Placer (measures and tapes the card on the wall), Recorder (writes each elevation and its distance from sea level).
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: Place cards
- Worksheet: Label it
- Worksheet: Try it at home
On the student sheet
- My prediction
- Our cards
- What did we find?
- The judges' ruling
- Exit ticket
- Place cards
- 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
- Represents elevation with integers
- Uses absolute value
- Distinguishes greater from further
From the lesson’s rubric, which scores each one as not yet, getting there or got it.
Questions teachers ask
How long does “Which is further from sea level?” take?
50–60 min. Group size: teams of 3.
How much prep does it need?
15 minutes: tape a strip of paper (or a row of taped sheets) 2.1 m tall on a wall. Mark sea level, 0, 1.1 m up from the bottom of the strip, and mark every 10 cm above and below it; each 10 cm stands for 1,000 m. Label +1000, +2000 … up to +9000 and −1000 … down to −11000. Print and cut the Place cards from the Worksheet, one set for the class, and have tape ready.
What materials do I need?
Place cards (from the Worksheet); paper strip or taped sheets, 2.1 m tall, and masking tape; ruler or metre stick. Cost: free: paper, tape and a metre stick you already have.
Which curriculum standards does it cover?
Common Core Math (US): 6.NS.C.5, 6.NS.C.6 (partly) and 6.NS.C.7.
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”, “Our cards”, “What did we find?”, “The judges' ruling”, “Exit ticket”, “Place cards”, “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.