Likelihood Lab Slides Likelihood Lab
Measuring the Magic of Chance
Grade 7 | Probability Intervention
The Big Question
How do we use numbers to describe if something will happen?
Rain Today?
Rolling a 6?
Winning a Game?
The Master Scale
0
Impossible
1/2 (0.5)
Equally Likely
1
Certain
Unlikely
Likely
Experiment #1: Coin Flip
What is the chance of flipping a coin and getting Heads?
The Logic:
2 total outcomes (Heads or Tails)
1 outcome we want (Heads)
Math: 1 / 2
Where does it go?
"Equally Likely"
Experiment #2: Rolling Dice
Event: Rolling a 7 on a standard 6-sided die.
0
Impossible
The die only goes from 1 to 6!
"It can never happen."
The Lab Challenge
Where would these go?
Event A
The sun will rise tomorrow morning.
Event B
Picking a red marble from a bag of 100 blue marbles.
Event C
Guessing a True/False question correctly.
Event D
It will rain in the desert at least once this year.
Probability Path Worksheet Probability Path Worksheet
Grade 7 Tier 2 Intervention | standard 7.SP.C.5
NAME:
DATE:
Part 1: The Probability Language
Draw a line to match the probability word to its numeric value.
Impossible
1/2 or 0.5
Equally Likely
1
Certain
0
Part 2: The Probability Path
Place the letter of each event on the probability line below.
0 0.25 0.5 0.75 1
Impossible Unlikely Equally Likely Likely Certain
A
You roll a 6-sided die and it lands on a number 1, 2, 3, 4, 5, or 6.
B
A cat will fly over your school today like a bird.
C
Flipping a coin and it landing on "Tails".
D
Picking a blue marble from a bag that has 1 blue marble and 99 red marbles.
Part 3: Lab Experiment
Look at the spinner your teacher has. Answer the questions below.
Observe Your Lab Spinner
1. How many total sections?
2. How many are BLUE?
Calculate & Place:
What is the probability of spinning BLUE?
/
Circle the best word for this probability:
Impossible Unlikely Equally Likely Likely Certain
Reasoning Challenge:
If an event has a probability of 0.8, is it more likely to happen or more likely to NOT happen? Why?
Chance Check Teacher Guide Chance Check Teacher Guide
Tier 2 Intervention | Grade 7 Probability
Learning Objective
Students will understand that probability is a measure between 0 and 1, where 0 is impossible, 1 is certain, and 0.5 is equally likely. Students will quantify likelihood using fractions and decimals.
Required Materials
Standard 6-sided dice
Standard coins (pennies/quarters)
4-section colored spinners
Blue/Red marbles and opaque bags
Standard Alignment
Colorado 7.SP.C.5
Key Vocabulary
Impossible (0)
Unlikely (< 0.5)
Equally Likely (0.5)
Likely (> 0.5)
Certain (1)
Instructional Flow
1
The Anchor Concept (10 min)
Use the Likelihood Lab Slides to introduce the 0-1 scale. Focus on the "Physicality" of the line. 0 is a brick wall (nothing happens), 1 is a guaranteed outcome.
Prompt: "If I tell you there is a 0% chance of a snowstorm today, should you wear your snow boots?"
2
Hands-On Manipulatives (15 min)
Hand out dice. Ask students to roll for a "7". When they realize it's impossible, point to the 0 on the Probability Path Worksheet .
Repeat with coins for "Equally Likely". Transition to the worksheet's part 3 (Spinner Lab).
3
Scaffolded Mapping (10 min)
Guide students through Part 2 of the worksheet. If a student struggles with "Unlikely" vs "Likely", use a bag of 10 marbles (9 red, 1 blue) to visualize the distance from 0.
Common Misconceptions
Scale Confusion
Students often think 1 is "a small chance" because it's a small number. Remind them that in probability, 1 is "100%" or "The Whole Thing."
Equally Likely ≠ Random
Students may think everything is "Equally Likely" because "anything could happen." Use the 1-blue/99-red marble bag to disprove this.
Progress Monitoring
Skill Look-Fors Correction Strategy Vocabulary Usage Can the student correctly label an event as "Impossible" or "Certain"? Use real-world examples (sun rising, pigs flying). Scale Placement Does the student place 0.5 exactly in the middle? Relate to money (50 cents is half of a dollar).
Odds Tracker Exit Ticket Exit Ticket
Odds Tracker
Checking your Probability Lab Skills
Name:
Date:
1
An event has a probability of 0.05.
Which word best describes this event?
Impossible
Unlikely
Likely
Certain
2
Place an "X" on the line where a Certain Event would be.
0 0.5 1
3
Create an Experiment!
Draw or describe a spinner where the probability of landing on GREEN is 1/4.
Why did you design it this way?
