Back to the lesson plan builder
Lesson length30 min45 min60 min

Print the plan for yourself; the student sheet prints on its own page after it.

Science lesson plan · 8th grade (Year 9 in England) · 30 minutes

Group 1: the alkali metals and their trend

Atoms, elements and the periodic table

CCSS NGSS.MS-PS1-1CCSS NGSS.HS-PS1-1England: KS3 Chemistry: The periodic tableEngland: GCSE Combined Science: Atomic structure and the periodic table

Objective and success criteria

Students will: Group 1: the alkali metals and their trend.

  • I can answer questions on today's skill on my own, without help.
  • I can explain each step and say why it works.
  • I can check my answer and spot a mistake.

Before and after

Needs first: The periodic table: groups and periods

Leads to: the next skill in this area.

Materials: Periodic tables, Atom model kits, Mini whiteboards, A diagram or short video clip of the idea, Printed student sheet (below).

Warm-up · 4 min

  • Quick retrieval from earlier learning (The periodic table: groups and periods). Students answer on mini whiteboards.
  • Show answers together and note who needs support in the main task.
  1. Which family does lithium belong to? (alkali metals (group 1) / halogens (group 17, also called group 7) / noble gases (group 18, also called group 0)) → alkali metals (group 1)Prompt: Is it a soft metal, a coloured reactive non-metal, or an unreactive gas?
  2. Which family does neon belong to? (alkali metals (group 1) / halogens (group 17, also called group 7) / noble gases (group 18, also called group 0)) → noble gases (group 18, also called group 0)Prompt: Is it a soft metal, a coloured reactive non-metal, or an unreactive gas?
  3. Which family does sodium belong to? (alkali metals (group 1) / halogens (group 17, also called group 7) / noble gases (group 18, also called group 0)) → alkali metals (group 1)Prompt: Is it a soft metal, a coloured reactive non-metal, or an unreactive gas?

Hook · 3 min

  • Show the periodic table and ask what patterns students can see before anything is explained.
  • Share the objective: Group 1: the alkali metals and their trend. Read the success criteria together.

I do: model it · 7 min

  • Work through the example out loud, saying why you do each step, not just what you do.
  • Example: Complete the word equation: lithium + water → ? + hydrogen
  • Step 1: alkali metal + water → metal hydroxide + hydrogen
  • Step 2: So the answer is: lithium hydroxide
  • Answer: lithium hydroxide
  • Pause after each step and ask a student to say what comes next.

We do: guided practice · 6 min

  • Do these together. Students try each step on whiteboards before you reveal it.
  • Use the hints as prompts rather than giving the answer.
  1. Complete the word equation: sodium + water → ? + hydrogen → sodium hydroxidePrompt: The solution left is alkaline.
  2. Lithium fizzes gently in water, sodium melts into a ball and whizzes around, and potassium bursts into a lilac flame. What does this show? (Potassium is not in group 1 / Reactivity decreases down group 1 / All group 1 metals react the same / Reactivity increases down group 1) → Reactivity increases down group 1Prompt: The order is lithium, sodium, potassium going down.

You do: independent practice · 7 min

  • Students work on the student sheet. Circulate and check the first two answers of every student early.
  • Students who finish: write a question of their own for a partner, with the answer.

The 6 questions are on the student sheet below, with answers in the key.

Exit ticket · 3 min

  • Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
  1. Lithium fizzes gently in water, sodium melts into a ball and whizzes around, and potassium bursts into a lilac flame. What does this show? (Reactivity increases down group 1 / Potassium is not in group 1 / All group 1 metals react the same / Reactivity decreases down group 1) → Reactivity increases down group 1Prompt: The order is lithium, sodium, potassium going down.
  2. Complete the word equation: potassium + water → ? + hydrogen → potassium hydroxidePrompt: The solution left is alkaline.

Watch out for

  • Everyday meanings of words getting in the way of the science meaning: define key words explicitly.
  • Remembering facts without the reason: ask "why?" and "what is the evidence?"

Support and stretch

Support

  • Review first: The periodic table: groups and periods.
  • Use concrete materials: periodic tables.
  • Give the first step of each question, or a partly worked example to finish.
  • Pair with a confident partner for the guided practice.

Stretch

  • Explain a common mistake in writing and how to fix it.
  • Write a word problem that uses today's skill, then solve a partner's.

Homework and more practice

Free online practice with hints and printable worksheets for this skill: eurekami.com/science/grade-8.

Free lesson plan from eurekami.com/lesson-plan-builder

eurekami

Group 1: the alkali metals and their trend

Name

Date

Score/ 6

  1. Question 1

    Why are alkali metals stored under oil?

    • A. to keep them warm
    • B. to make them shiny
    • C. to stop them reacting with oxygen and water vapour in the air
    • D. because they are liquids
  2. Question 2

    Complete the word equation: potassium + water → ? + hydrogen

    Answer

  3. Question 3

    The alkali metals: which statement is NOT true?

    • A. Alkali metals react with water to make alkaline solutions.
    • B. Group 1 metals are soft enough to cut with a knife.
    • C. Group 1 metals have two outer electrons.
    • D. Sodium is less dense than water, so it floats.
  4. Question 4

    Lithium fizzes gently in water, sodium melts into a ball and whizzes around, and potassium bursts into a lilac flame. What does this show?

    • A. Reactivity increases down group 1
    • B. Potassium is not in group 1
    • C. Reactivity decreases down group 1
    • D. All group 1 metals react the same
  5. Question 5

    Complete the word equation: sodium + water → ? + hydrogen

    Answer

  6. Question 6

    Complete the word equation: sodium + water → sodium hydroxide + ?

    Answer

Free from eurekami.com

for the adult only

Answer key: Group 1: the alkali metals and their trend

  1. 1. C. to stop them reacting with oxygen and water vapour in the air

  2. 2. potassium hydroxide

  3. 3. C. Group 1 metals have two outer electrons.

  4. 4. A. Reactivity increases down group 1

  5. 5. sodium hydroxide

  6. 6. hydrogen