Introduction to Reactions

Curriculum Area: Science | Level 4 (Aligned with The New Zealand Curriculum)

Big Idea: Chemistry and Biology are dynamic bodies of knowledge that use unique models and language to explain the material and living environment.

Achievement Objective:

• Students will understand that materials can be changed physically and chemically, and chemical changes involve the formation of new substances.
• Students will use a variety of simple symbols and equations to represent chemical reactions.

---

Lesson Overview (60 minutes)

This engaging first lesson in the "Chemical Reactions Unleashed" unit introduces Year 9 students to chemical reactions in a hands-on and interactive way. Students will explore real-world examples of reactions, participate in an energetic class demonstration, and collaboratively investigate key scientific concepts in a dyslexia-friendly learning environment.

---

Lesson Plan

1. Hook (10 minutes) – Captivating Introduction

Objective: Engage students and activate prior knowledge.

✅ Activity: "The Disappearing Coke Can Trick" (Teacher Demo)

• Place an empty aluminium can into a beaker of hydrochloric acid (or use a safer substitute like vinegar and baking soda in a sealed bottle for visual effect).
• Ask: What do you observe? "What will happen next?"
• Let students discuss their predictions in pairs, then share aloud.

🧠 Dyslexia Support:

• Use a large, bold font on the board with minimal text (a simple question: "What do you think is happening?").
• Avoid fast-paced verbal explanations. Instead, describe the experiment in short, clear steps.
• Offer a sketched diagram of the setup for visual support.

---

2. Explore (15 minutes) – Everyday Reactions

Objective: Help students recognise that chemical reactions happen everywhere.

✅ Activity: Reaction Sort & Discussion

• Give students pre-written scenario cards with various chemical and physical changes (e.g., baking bread, ice melting, iron rusting, a glow stick glowing).
• In pairs, students sort the examples into two categories: "Chemical Change" and "Physical Change."
• Discuss as a class – teacher clarifies misconceptions.

🧠 Dyslexia Support:

• Use coloured cards with simple words & pictures to reinforce meaning.
• Keep instructions short & step-based.
• Offer verbal and written choices to reduce reading load.

---

3. Explain (10 minutes) – Understanding Chemical Reactions

Objective: Introduce key terms – reactant, product, evidence of chemical change.

✅ Activity: Simple Breakdown

• Teacher Explanation: "A chemical reaction happens when two things mix and make something new. The old materials (called reactants) turn into something new (called products)."
• Write a basic model on the board:
  Reactants → Products (with a simple example – baking soda + vinegar = bubbles).
• Ask for student-friendly examples (e.g., "Who has seen flames on a fire? That’s a reaction too!").

🧠 Dyslexia Support:

• Use colour-coding for ‘Reactants’ and ‘Products’ to distinguish them.
• Provide a large, simple word-matching activity for key terms at the end of the explanation (reactant = starting materials, product = new materials).

---

4. Apply (15 minutes) – Interactive Group Challenge

Objective: Reinforce reaction concepts through hands-on exploration.

✅ Activity: Mini Chemical Reaction Stations (3 small experiments – students rotate through each in groups of 6)

1. Fizzing Magic: Baking soda and vinegar (gas formation).
2. Colour Change: Cabbage indicator + vinegar or baking soda (acid-base reactions).
3. Temperature Shift: Dissolving salt in water vs. mixing calcium chloride and water (exothermic vs. endothermic).

Each station includes a worksheet with tick-box answers rather than long-written responses for accessibility.

🧠 Dyslexia Support:

• Replace complex instructions with step-by-step pictorial cards.
• Ensure groups include a reading buddy/talker for those who struggle with instructions.
• Simplify answers into "What did you see?" checklists rather than open-ended writing.

---

5. Reflect (10 minutes) – Bringing It All Together

✅ Activity: 3-Word Summary Exit Ticket

• Each student must write 3 words that sum up today’s lesson (e.g., "bubbles, heat, change").
• Share words in a quick popcorn round.

🧠 Dyslexia Support:

• Offer a printed visual word bank as a scaffold.
• Allow students to draw instead of writing if needed.

---

Assessment & Next Steps

✅ Formative check:

• Observe participation in the discussion and hands-on activity.
• Encourage students to explain a reaction in their own words in pairs.

📌 Next Lesson: Investigating reaction types! 🚀

---

Teacher Reflection & Adaptations

• Did students grasp the idea of reactants and products?
• Were dyslexic students supported effectively (visuals, step-based support, reading alternatives)?
• Adjust pacing if needed for future lessons.

🎉 Bonus Idea: Next time, allow students to suggest a household reaction for a demo!