Probability – Grade 7 math lesson
Lesson 17 of 21 in the Grade 7 math course
US version. US grades, US spelling and dollars ($). · UK Maths Department
A complete 45-minute lesson for grade 7 (ages 12–13) that runs on this page – at school or at home. Every answer is graded right away, with a worked explanation.
- Time
- 45 minutes + 20 min homework
- Grade
- Grade 7 (ages 12–13)
- You need
- Paper, a pencil and this page
- Graded
- Instantly, with explanations
For parents: how to use this lesson
You don't need to know this topic yourself. The lesson explains each step on screen, one tidy step at a time. Every answer is graded straight away with a worked explanation, so you never have to grade anything.
- Read what your child will learn and the big ideas together.
- Press Start the lesson below and sit with your child for the teaching and the worked examples (about 19 minutes).
- Let them do the practice on their own. They choose Getting started, On track or Challenge – start on On track and move up after a few right in a row.
- Finish with the exit ticket and the talk question: “Is it harder to roll a 6 than a 1? Why or why not?”
- Later that day or the next day: the homework (20 minutes), then a practice test.
Watch out for
- Thinking every event is 50 : 50 because it "happens or not". Count the outcomes: rolling a 6 is 1 out of 6.
- Writing a probability bigger than 1. Probabilities are always between 0 and 1.
Tip for home: Talk about weather forecasts: what does a 70% chance of rain mean?
What your child will learn
Learning goal: find and use probabilities of single events.
Success looks like
- I can use the probability scale.
- I can calculate a probability.
- I can use P(not A) = 1 − P(A).
Key words
- probability
- how likely an event is, from 0 to 1
- outcome
- one possible result
- event
- one or more outcomes
- equally likely
- each outcome has the same chance
What to have ready
- Paper and a pencil
- This page on a computer, tablet or phone
- For the hands-on part: Roll a dice or spin a spinner and compare what happens with the probabilities you worked out.
The big ideas (for the adult)
Probability measures how likely something is, from 0 (impossible) to 1 (certain).
When outcomes are equally likely, probability = number of ways it can happen ÷ total number of outcomes.
The probabilities of all the outcomes add up to 1, so P(not A) = 1 − P(A).
The lesson, step by step
| Part | Time | How it is checked |
|---|---|---|
| Starter: quick recall | 5 min | Graded by Classfern |
| Teaching input | 10 min | Not assessed, self-checked |
| Worked examples and guided practice | 9 min | Not assessed, graded by Classfern |
| Independent practice | 15 min | Graded by Classfern |
| Closure and exit ticket | 6 min | Graded by Classfern, self-checked |
Starter, "your turn", practice and exit ticket are graded by Classfern. Worked examples and teaching are not assessed. The hands-on task and the reflection are self-assessed. Explanations in talk are judged by the parent and not recorded.
The lesson
It runs here on the page. No sign-up and no names – progress is kept only in this browser.
Homework and practice at home
20 minutes: 10 practice questions, 3 multiple-choice questions and 2 to remember from earlier work, then a short reflection. New questions every time, all graded instantly.
More practice
More Grade 7 math lessons
- Ratios
- Percent
- Proportional relationships
- Operations with integers
- Repeating decimals
- Evaluating expressions
- Simplifying expressions
- Expanding expressions
- Solving equations
- Inequalities
- Scale drawings and maps
- Angle relationships
- Area of triangles, parallelograms and trapezoids
- Circles: circumference and area
- Volume and surface area
- Cross sections of 3-D figures
- Experimental probability
- Compound events
- Box plots and interquartile range
- Sampling and making inferences
Curriculum
Common Core State Standards 7.SP.C.5: “Understand that the probability of a chance event is a number between 0 and 1 that expresses the likelihood of the event occurring. Larger numbers indicate greater likelihood. A probability near 0 indicates an unlikely event, a probability around 1/2 indicates an event that is neither unlikely nor likely, and a probability near 1 indicates a likely event.”
Common Core State Standards 7.SP.C.7.a: “Develop a uniform probability model by assigning equal probability to all outcomes, and use the model to determine probabilities of events. For example, if a student is selected at random from a class, find the probability that Jane will be selected and the probability that a girl will be selected.”
Our lessons and questions are our own. They are not written or endorsed by any government department, testing agency or exam board.