Mold Growth Inquiry

Lesson Overview

Students will design a safe experiment testing mold growth under varying conditions. Through hands-on exploration, they will develop scientific observation skills, understand factors affecting food spoilage and storage, and recognize the importance of sanitation to prevent cross-contamination.

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Standards Alignment

Next Generation Science Standards (NGSS) & Common Core Integration:

• MS-LS1-5: Construct a scientific explanation based on evidence for how environmental and genetic factors influence growth of organisms.
• MS-ETS1-2: Evaluate design solutions based on criteria and constraints.
• CCSS.ELA-LITERACY.RST.6-8.3: Follow precisely a multistep procedure when carrying out experiments, taking measurements, or performing technical tasks.
• CCSS.ELA-LITERACY.WHST.6-8.7: Conduct short research projects to answer a question, drawing on several sources and generating additional related, focused questions.
• CCSS.MATH.PRACTICE.MP2: Reason abstractly and quantitatively when recording and interpreting observations.

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Learning Objectives (I Can Statements)

• I can set up a controlled scientific experiment to observe mold growth safely.
• I can identify and describe factors that speed up or slow down mold growth on food.
• I can record detailed daily observations using charts and sketches.
• I can explain how proper food storage and sanitation prevent food spoilage and contamination.
• I can communicate my findings clearly through discussion and written summaries.

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Success Criteria

• Set up four mold test conditions correctly and safely.
• Complete daily observations using the provided chart for at least 7 days.
• Describe how moisture, temperature, and hygiene affect mold growth using evidence from the experiment.
• Demonstrate understanding of food safety rules by following hygiene and disposal procedures.
• Participate actively in group discussions and share experimental predictions and conclusions.

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Materials (per group of 2–3 students)

• 4 slices of store-bought bread (white and/or whole wheat) or apple slices
• 4 sealable quart-size plastic bags
• Masking tape + marker for labeling
• Spray bottle with clean water
• Disposable gloves (optional but recommended)
• Paper towels
• School science goggles (if required)
• Storage locations (dark cabinet, sunny window, warm spot)
• Observation charts (printed dyslexia-friendly format with clear fonts and spacing)

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Vocabulary

• Mold
• Spoilage
• Cross-contamination
• Sanitation
• Control group
• Variables (moisture, temperature, hygiene)

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Lesson Procedure (48 minutes total)

1. Engage (5 minutes)

• Begin by asking: “Have you ever seen mold on food at home? What do you think causes it?”
• Briefly introduce the experiment title: “How Fast Does Mold Grow?”
• Discuss why food safety and hygiene are important to prevent contamination and illness.

2. Safety & Hygiene Review (5 minutes)

• Explicitly teach safety rules: no opening sealed bags, washing hands before and after, wearing gloves optionally.
• Explain disposal method to keep experiment safe and household mold only.
• Distribute gloves and goggles if school policy requires.

3. Experiment Setup Instructions (8 minutes)

• Provide step-by-step instructions for preparing bags A-D:
  • Bag A: Dry bread (Control)
  • Bag B: Damp bread (Lightly misted)
  • Bag C: Warm location bread (dry or damp, placed by heat or sunny window)
  • Bag D: Clean vs. dirty hands bread touches, bag separately
• Model correct labeling and sealing techniques using masking tape and marker.
• Students work in groups to prepare their four bags. Teacher circulates to assist.

4. Observation Training (5 minutes)

• Distribute dyslexia-friendly observation charts with spaces for date, sketching mold, color, amount (none/small/widespread), and notes.
• Demonstrate how to record observations clearly and consistently without opening bags.
• Highlight importance of daily recording for 7–10 days.

5. Group Prediction & Hypothesis Discussion (5 minutes)

• Ask groups to discuss:
  • Which bread condition will grow mold fastest?
  • Why do they expect moisture, temperature, or hygiene to influence mold?
• Groups write brief hypotheses on their observation sheets.

6. Wrap Up & Clean Up (5 minutes)

• Confirm everyone's mold bags are sealed securely and stored appropriately (teacher collects or students put in designated spots).
• Review hygiene rules again: washing hands after setup and proper disposal at experiment’s end.
• Remind students when and how to complete daily observations independently or during class.

7. Formative Assessment & Exit Ticket (5 minutes)

• Students write a quick exit ticket responding to:
  “What is one important rule about food safety and hygiene that helps prevent mold and illness?”
• Collect exit tickets for review.

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Differentiation Strategies

• For students with dyslexia: Use dyslexia-friendly fonts and color-coded charts with visuals; provide oral instructions and recorded videos of steps.
• For ELL students: Pair with bilingual peers or provide vocabulary picture cards; use clear step-by-step directions with visuals.
• For students with behavioral needs: Assign consistent group roles, use checklists, and provide quiet workspace areas.
• For advanced learners: Challenge to research and report on types of molds and their risks or design a new condition to test (e.g., bread in fridge).

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Extension Activities

• Design a follow-up project on how preservatives affect mold growth (e.g., comparing fresh vs. packaged bread).
• Create informational posters for family about safe food storage and sanitation to display at home.
• Conduct mini-research on illnesses caused by food-borne molds and prevention methods.
• Use a microscope or digital images to explore mold structures for a science fair project.

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Reflection for Teachers

• Monitor group collaboration and safety compliance closely.
• Use student journals and charts to assess understanding of scientific methods and food safety connections.
• Plan follow-up lessons on microbiology, nutrition, or health sciences based on student interest sparked by this experiment.

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By incorporating interactive science inquiry aligned with NGSS and Common Core standards, this lesson empowers 8th graders with practical life skills and critical thinking about everyday phenomena that affect health and safety.