🌿Lesson 3 — The plant that plays itself

Grade Band: 3-8 · Duration: 60 min · Device: Biotron · Standards: NCAS MU:Re7.1.5a, NGSS 4-LS1-1, NGSS MS-LS1-3, ISTE 1.5

Enduring Understanding

Living things produce tiny electrical signals all the time. Biotron makes those signals audible. The plant is doing the same thing it always does — we are listening differently.

Essential Question

If we changed what we measure, would every living thing have a "song"?

Learning Objectives

Students will be able to:

1. Set up Biotron on a houseplant and trigger sound by touching or moving near the plant.
2. Identify three variables that change the plant's signal (touch, light, water, proximity).
3. Record at least one minute of plant audio and reflect on what changed when they intervened.

"I Can" statements:

• I can connect a plant to a computer through Biotron.
• I can name two things I did that made the plant's song change.

Vocabulary

• Bio-electric signal — the tiny voltage living cells produce as they work.
• Sensor — a device that detects a physical signal and makes it usable.
• Variable — a thing we change to see what happens.
• MIDI — Musical Instrument Digital Interface, the digital language of musical notes.

Materials & Setup

• One Biotron per group of 4 students (plan for 7-8 groups; the Class Pack 30 ships with 3 Biotrons — rotate groups in stations).
• One leafy houseplant per Biotron — pothos, monstera, philodendron, or a basil plant from the cafeteria.
• Laptop with browser piano per group.
• Worksheet: "What did you change? What did you hear?" (provided in PDF download).
• Teacher prep (10 min): Water plants 30 minutes before class (dry plants give weak signal). Clip leaf-pads to one leaf on each Biotron. Volume up to quiet, not loud — the plant's voice rewards listening.

Lesson Procedure

1. Engage — listen first, no explanation (5 min)

Lights down. Teacher plays a recording of a plant on Biotron from another classroom (or your own pre-recording — even 30 seconds is enough). Students close their eyes. Ask after: "What did you hear? Did it sound like music or like something else?" Collect 4-5 observations.

2. Explore — what is the plant doing? (15 min)

Teacher reveals Biotron + the plant. Demonstrates touching a leaf, moving a hand close to the plant without touching, turning a light on and off, blowing gently on the plant. Each one changes the sound.

Whole-class share-out: "Which one surprised you?" Introduce bio-electric signal: living cells make tiny voltages, the plant changes its voltage when you touch it, the device hears the change and turns it into music.

3. Investigate — variables and recordings (25 min)

Groups of 4 rotate through Biotron stations. Each group has 5 minutes per station with a worksheet:

One student per group records 30 sec of audio per variable using a phone or browser recorder.

4. Share — what does the plant know? (15 min)

Each group plays back one recording for the class and reads their worksheet observation. Teacher writes the variables on the board with the verbs students used ("the sound got busier when we touched it," "quieter when we covered the light").

Close with the Essential Question: "If we measured a different thing — say, breath, or sweat — would you have a song?"

Assessment

• Formative: Worksheet completion (variable column filled for at least 3 variables).
• Summative: Exit ticket — one written sentence per student: "The plant changes its song when ___." Grading on MU:Re7.1.5a (responding to musical works with context).

Differentiation & UDL

• Support: Pre-fill the variable column on worksheets; students fill only the "what we heard" column.
• Stretch: Advanced groups download free DAW (GarageBand / Soundtrap free) and import their plant recording. Add a drum loop. Compose a 60-sec piece.
• Access: A student with mobility differences becomes the "audio engineer" — runs the recording app, manages the laptop. A student with sensory sensitivity uses headphones and reports back to the group.

Extension & cross-curricular links

• Science (NGSS MS-LS1-3): Body systems and organisms — extend with: research one other organism that produces electrical signals (electric eel, your own heart, etc.).
• Math: Plot the audio volume over time using free software (Audacity). Compare two recordings — what's quantitatively different?
• ELA / SEL: Free-write — "What would your song sound like if a sensor could hear your day?"
• Take-home: Send each student home with one prediction: "What plant in your house do you think would make the most interesting song?"

Teacher Notes

• Snake plants are quiet but resonant. Aloe is barely audible. Pothos is reliable. Monstera is showy.
• The plant takes about 90 seconds to calibrate when you first plug Biotron in — quiet during that time is normal, don't panic.
• Bio-electric signals are not dangerous. Voltages are millivolts — far below anything you'd feel. Reassure anxious parents in advance with a one-paragraph note.
• The plant doesn't get harmed by Biotron. Leaf-pads don't pierce the leaf. Reusable.