DNA Extraction Lab

Unlock the blueprint of life—using fruit and everyday materials! In this inquiry-driven lab, students extract real DNA from strawberries using simple kitchen supplies. By smashing cells, dissolving membranes, and spooling DNA strands from solution, students get hands-on with molecular biology in a way that’s visual, tangible, and unforgettable.

Through guided analysis and reflective questions, students uncover the “why” behind each step of the process—then explore how DNA extraction plays a vital role in medicine, agriculture, forensics, and more.

Why Teachers Love This Activity:

• Visible DNA = Powerful Learning – Students see the molecule they’ve been learning about, making abstract genetics concepts real and concrete.
• Built-In Scientific Thinking – From pre-lab predictions to post-lab reflections, students develop and apply inquiry skills throughout the activity.
• Real-World Relevance – Connects classroom biology to biotechnology, genetic testing, crime scene investigations, and agricultural science.
• Standards-Aligned & Easy to Run – Supports NGSS standards for molecular biology, heredity, and cellular structure, using only common household supplies.
• Low-Cost, High-Impact – Uses strawberries, soap, salt, water, and rubbing alcohol—budget-friendly, no fancy tools required.

How It Works:

• Break Cells Open – Students gently mash strawberries to physically break open the cells.
• Dissolve Membranes – A homemade extraction solution of soap and salt dissolves cell and nuclear membranes, releasing DNA into the liquid.
• Separate & Filter – The mixture is poured through a coffee filter to remove solid debris and isolate the DNA-containing solution.
• Precipitate the DNA – Cold rubbing alcohol is carefully added to the filtered liquid, causing DNA to rise as white, stringy strands that can be spooled with a stick.
• Observe & Reflect – Students sketch, describe, and analyze what they see, explain why each ingredient was used, and explore how DNA extraction applies to modern science.

What’s Included:

• Student Lab Packet – Engaging pre-lab questions, step-by-step procedures, built-in questions throughout, and scaffolded post-lab reflection
• Answer Key & Teacher Tips – Setup guidance, suggested responses, and optional extensions
• Materials List & Safety Guidelines – All using grocery-store items, perfect for limited-resource classrooms
• Short Research Prompts – Connect students’ experiences to real-world applications like genetic disease research, DNA fingerprinting, and GMOs

Why Students Will Love It:

• “I Can See DNA!” – Watching cloudy, stringy DNA rise from a pink strawberry mixture feels like magic—while building real science skills.
• Hands-On, Messy (but Safe) Fun – Students love the tactile, visual nature of the activity—from mashing fruit to spooling DNA.
• It Feels Like Real Science – This isn’t just a classroom demo—it mirrors protocols used in modern biotech labs.

Materials (per group):

• 3-4 strawberries (previously frozen and thawed are best)
• 1 resealable plastic bag
• 2 tsp dish soap
• ½ tsp salt
• ½ cup water
• 1 clear plastic cup
• 1 coffee filter or paper towel
• 1 funnel (or DIY version)
• 1 wooden skewer or stick
• Cold rubbing alcohol
• Measuring spoons, stirring stick
• Goggles, paper towels for clean-up

Pro Tip: Pre-freeze alcohol the night before and use thawed frozen strawberries for best results. Start class with a mystery question on the board: “Can you see DNA?” Let students guess—then dive into the lab and let the reveal wow them.

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If you have any questions, please do not hesitate to ask.
Thanks for visiting!
Jessica