Lesson plan — Probability: The 0–1 Scale, Experiments & Simulations

Explicit teaching — I Do (~15 min)

1. The 0–1 chance scale WA6MPSP1

A probability scale from 0 (impossible) through 1/2 (even chance) to 1 (certain) with everyday events placed along it. — Every chance event sits somewhere from 0 to 1.

Draw a line from 0 (impossible) to 1 (certain), with 1/2 (even chance) in the middle. Place everyday events: "the sun will rise tomorrow" (≈1), "I roll a 7 on a normal die" (0), "a coin lands heads" (1/2), "it rains today" (somewhere between). Connect to fractions and decimals from Lesson 1.

2. Expected vs observed WA6MPSP2

Demonstrate setting up a tally for a simulation.

Guided practice — We Do (~20 min)

Order the events. As a class, place a set of event cards on the 0–1 scale and justify positions using fractions.
Predict then test. Predict the expected fraction for a die showing an even number (1/2). In pairs, roll 20 times and tally.
Pool the data. Combine all pairs' results into a class total (hundreds of trials) and compare the class observed fraction to 1/2 — discuss why the larger sample is closer.
Unequal spinner. Examine a spinner with unequal sectors; reason about which outcome is more likely and where it sits on the scale.

Independent practice — You Do (~15 min)

Worksheet/task:

place given events on a 0–1 scale and assign a fraction/decimal to each;
run a chance experiment (coin, die or spinner), tally results, and record the observed fraction;
compare observed with expected and write a sentence about variation;
predict what would happen with many more trials.