Substitute Lesson Plan: Introduction to Probability

Grade: 7th Grade Math
Resource: Grade 7 Math Student Workbook — Chapter 1, Section 1.1 ("Investigate Chance Processes. Develop/Use Probability Models"), specifically activity 1.1a Class Activity: Using Data to Make Predictions (Probability), p. 8

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Objective

Students will understand that probability is a number between 0 and 1 that describes how likely a chance event is to occur, with numbers near 0 meaning unlikely, numbers near ½ meaning neither likely nor unlikely, and numbers near 1 meaning likely. Students will begin distinguishing between theoretical probability and experimental probability using data.

Materials

• Grade 7 Math Student Workbook, Chapter 1, Section 1.1a (Class Activity, p. 8, and Homework, p. 12)
• Pencils
• Paper for notes/exit ticket
• (Optional, if available) coins, dice, or spinners referenced in the workbook activity — if not available, students can work from the data/tables printed in the workbook itself

Warm-up (~5 min)

1. Write the word PROBABILITY on the board.
2. Ask students to individually jot down: "What do you think this word means in math? Can you think of an example from everyday life where people talk about 'chances' or 'likelihood'?"
3. Call on 2–3 volunteers to share their examples aloud.
4. Introduce the key vocabulary words students will see today, writing them on the board: chance, probability, outcome, frequency, theoretical probability, experimental probability. Tell students they don't need to know definitions yet — today's activity will help build understanding.

Main Activity (~25 min)

1. Have students open their workbooks to Section 1.1a: Class Activity – Using Data to Make Predictions (Probability), page 8.
2. Explain to the class the core idea from the chapter introduction: probability is always a number between 0 and 1 (or 0% and 100%) that tells us how likely something is to happen — a probability near 0 means unlikely, near ½ means neither likely nor unlikely, and near 1 means likely.
3. Have students work in pairs or small groups (groups of 2–3 work well) to work through the activity on page 8 as written in the workbook.
4. Circulate around the room while students work. Since this is a review/introductory activity, encourage students to:
5. Read each part of the activity carefully before answering.
6. Discuss with their partner why an outcome might be more or less likely.
7. Use the data given in the workbook to make predictions, rather than guessing.
8. With about 8 minutes left in this block, pause the class and ask 1–2 groups to briefly share one prediction they made and how they used the data to support it.
9. If groups finish early, direct them to begin 1.1a Homework: Probability Predictions (page 12) quietly at their seats.

Wrap-up / Exit Ticket (~10 min)

1. Have students clear their desks except for a blank sheet of paper and a pencil.
2. On the board, write this Exit Ticket prompt:
3. "In your own words, explain what it means if a probability is close to 0. What does it mean if a probability is close to 1? What does it mean if it's close to ½?"
4. Give students 5–7 minutes to write their responses individually.
5. Collect the exit tickets as students leave, or have them place them in a designated bin/tray.
6. Remind students that Section 1.1a Homework (page 12) should be completed if not finished in class, as it continues today's topic of probability predictions.

If Time Remains

Ask students to look back at the vocabulary words listed on the board (chance, probability, outcome, frequency, theoretical probability, experimental probability). Have them choose two of the words and write one sentence for each, using the word correctly based on what they learned in today's activity. Volunteers can share their sentences aloud with the class.