Overview (for teacher & student)
These are eight student-facing Cornell note-taking experiment worksheets (two per experiment) designed for a 13‑year‑old (Year 8) using MEL Science kits and historical context from C. H. Haskins. Each experiment pack includes:
- Worksheet A — Pre‑lab Cornell (background, hypothesis, variables, method outline, safety)
- Worksheet B — Post‑lab Cornell (data table, observations, analysis, conclusion, evaluation)
Each worksheet includes: ACARA v9 learning‑area mapping (by strand and descriptive outcome), a firm teacher comment written in a direct, high‑expectation tone (Amy Chua cadence — stern but constructive), and an extended rubric with four achievement levels.
ACARA v9 mapping (summary — Year 7–8 focus)
- Science Understanding — Chemical sciences: properties and reactivity of metals; corrosion and protection; chemical reactions that transfer electrons (redox) and produce electricity.
- Science Understanding — Physical sciences: electricity as a flow of charge; cells and circuits.
- Science Inquiry Skills: Questioning and predicting; planning and conducting investigations; processing and analyzing data; evaluating results; communicating scientific ideas.
- Science as a Human Endeavour: Historical development of scientific ideas (use Haskins to connect medieval tools/experiments), applications and implications of science (corrosion protection, batteries).
Experiment 1 — Rust Protection (MEL Science: Corrosion)
Worksheet 1A — Pre‑lab Cornell
Title: Rust Protection — Which method best prevents iron corrosion?
Aim: To compare protection methods (paint, oil, galvanic sacrificial coating, control) to determine which best prevents rust in saltwater exposure.
Background (short): Corrosion is an oxidation reaction of iron forming iron oxides. Protection methods prevent oxygen/water contact or change electrochemical conditions. Read C. H. Haskins notes on historical approaches to metal preservation.
Vocabulary (write definitions in your Notes column): corrosion, oxidation, cathode, anode, sacrificial protection, electrolyte, barrier coating.
Hypothesis (clear & testable): Write a sentence predicting which treatment will show the least mass change and least visible rust after 7 days in saltwater.
Variables:
- Independent: surface treatment (none, painted, oiled, sacrificial zinc)
- Dependent: visible rust score (0–5), mass change (g), time to first rust spot
- Controlled: same iron sample size, same saltwater concentration, temperature, immersion time
Materials: iron strips, paint, oil, zinc strip (for sacrificial), salt, water, scale, ruler, timer, safety goggles, gloves.
Safety: Wear goggles and gloves. Handle chemicals and metal edges carefully. Dispose of solutions per instructions.
Method (brief step list):
- Label samples: Control, Paint, Oil, Sacrificial.
- Apply treatments; record initial mass and appearance; photograph.
- Place in same saltwater container (or identical replicates) at room temperature.
- Observe daily; record rust appearance; reweigh at day 7.
Predicted results (left/cue column prompts for Cornell):
- Which sample will corrode fastest?
- Which will show least mass loss?
- How will you score rust appearance?
Notes column (main Cornell area): (Students: leave this large — record procedure modifications, observations, dates, times, photos/sketch references.)
Summary (after lab): One or two sentences summarising the purpose and predicted outcome.
ACARA v9 mapping (Experiment 1)
- Science Understanding: Chemical sciences — investigate reactivity and corrosion of metals and how treatments change reactivity.
- Science Inquiry Skills: Plan and conduct comparative tests; use fair test controls; record data and observations; present results.
- Science as a Human Endeavour: Historical methods of metal protection (Haskins) and modern applications.
Teacher comment (Amy Chua cadence — firm & constructive)
Do not write fuzzy hypotheses. Be precise: name the treatment and the measurable outcome. If your setup is sloppy, your data are useless. I expect exact masses, consistent labels, and daily observations. No excuses — plan, measure, and record properly.
Extended rubric — Rust Protection Pre‑lab (Worksheet 1A)
| Criterion | Excellent (4) | Proficient (3) | Developing (2) | Beginning (1) |
|---|---|---|---|---|
| Hypothesis | Clear, specific, measurable prediction (treatment + measure) | Clear prediction but less specific about measure | Testable but vague | No clear or testable hypothesis |
| Variables | All variables identified and controls specified | Most variables identified | Some variables missing or control unclear | Variables poorly identified |
| Safety & Materials | Complete materials list and safety steps | Mostly complete | Missing important items/safety steps | Incomplete |
| Method | Logical, repeatable steps with clear measurements | Clear steps but minor gaps | Steps unclear or missing measurements | Method not usable |
Worksheet 1B — Post‑lab Cornell
Title & Date: Rust Protection — Day 7 results
Data table (example columns to copy):
| Sample | Initial mass (g) | Final mass (g) | Mass change (g) | Rust score (0–5) | Time to first rust (days) |
|---|---|---|---|---|---|
| Control | |||||
| Paint | |||||
| Oil | |||||
| Sacrificial |
Observations (describe appearance, smell, photos/sketch reference):
Analysis questions (write short answers in Notes column):
- Which treatment showed the least mass loss and lowest rust score? Explain why (chemical reasoning).
- Was your hypothesis supported? Explain with data.
- How might electrolyte concentration or temperature have affected results?
- How do your results relate to historical preservation methods discussed in Haskins?
Calculations / Sample workings: Show mass change calculations and any percent loss.
Conclusion (1–3 sentences): State which treatment is best and why, referencing data.
Evaluation & Improvements: List at least two specific improvements (e.g., replicate more samples, constant temperature bath, uniform paint thickness).
Extension question (challenge): Design a follow-up experiment to test the longevity of the best treatment under acidic rain simulation.
Summary (bottom Cornell summary): Two‑sentence summary of outcomes and key learning.
ACARA v9 mapping (Experiment 1 — post):
- Process and analyze data; evaluate investigations; communicate findings using evidence.
Teacher comment (Amy Chua cadence — firm & constructive)
You measured; now interpret. Don’t offer vague explanations. Use the data: give numbers, show calculations, and state the chemical reason for differences. If you can’t explain it, rework your notes until you can. Excellence requires exactness.
Extended rubric — Rust Protection Post‑lab (Worksheet 1B)
| Criterion | Excellent (4) | Proficient (3) | Developing (2) | Beginning (1) |
|---|---|---|---|---|
| Data quality | Complete, accurate, units, replicates where needed | Mostly complete with minor errors | Some missing or inconsistent data | Data incomplete or incorrect |
| Analysis | Clear calculations, correct interpretation, links to chemistry | Good calculations and reasonable interpretation | Calculation errors or weak interpretation | No analysis or incorrect conclusions |
| Conclusion & Evaluation | Evidence‑based conclusion and specific, practical improvements | Evidence‑based conclusion, general improvements | Conclusion not well supported | Conclusion unsupported |
| Communication | Clear, concise summary; correct scientific vocabulary | Mostly clear; minor language issues | Some unclear sections | Poorly communicated |
Experiment 2 — Electricity vs Iron (MEL Science: Corrosion & Electricity Interaction)
Worksheet 2A — Pre‑lab Cornell
Title: Does an electric current affect the corrosion of iron?
Aim: Test whether passing a small DC current through an iron sample in an electrolyte increases or decreases corrosion rate.
Background: Electric current can change electrochemical potentials and may accelerate or inhibit corrosion depending on direction (cathodic protection vs. electrolysis). Consider safety with power supplies.
Hypothesis: (Write: e.g., ‘If iron is connected as the cathode/anode under X mA current, then corrosion will {increase/decrease} compared to control because…’)
Variables:
- Independent: presence and direction of applied DC current (none, current with iron as cathode, current with iron as anode)
- Dependent: rust score, mass change, visible bubble evolution
- Controlled: same electrolyte, current magnitude, duration
Materials & Equipment: iron electrode, power supply (low voltage DC), wires, clips, multimeter, electrolyte (saltwater), scale, stopwatch, protective equipment.
Safety: Low voltage only; never short power supply; wear eye protection; do not touch electrodes when powered; disconnect before adjusting.
Method (brief):
- Set up three cells: Control (no current), Iron as cathode (current applied), Iron as anode (current applied).
- Keep current constant (e.g., 50 mA); record voltage and current.
- Run for set time (e.g., 4 hours or daily observation period) and record mass/appearance.
Predictions / Cornell cues:
- What happens when iron is the cathode vs anode?
- How will bubbles look? Will mass increase/decrease?
Notes area: Log current readings, temperature, any irregularities.
ACARA v9 mapping (Experiment 2)
- Chemical and physical understanding: redox reactions and the role of electrical energy in driving chemical change.
- Inquiry skills: measurement of current/voltage, controlled experiments, safety in electrical setups.
Teacher comment (Amy Chua cadence)
Electric circuits are unforgiving. If your connections are sloppy you will get bad data. Check your current with a multimeter every time. I expect neat diagrams, labelled polarities, and a detectable, explained difference between cathodic and anodic setups. Work precisely.
Extended rubric — Electricity vs Iron Pre‑lab
| Criterion | Excellent (4) | Proficient (3) | Developing (2) | Beginning (1) |
|---|---|---|---|---|
| Electrical safety & setup | Clear wiring diagram, safety steps, correct anticipated current | Diagram present, minor omissions | Incomplete diagram or safety steps | No reliable plan |
| Hypothesis & rationale | Specific hypothesis linked to redox/electrochemistry | Good hypothesis with some reasoning | Weak links to chemistry | No clear rationale |
| Variables & controls | All well described | Mostly complete | Some missing | Poor |
Worksheet 2B — Post‑lab Cornell
Data Table (example):
| Setup | Current (mA) | Initial mass (g) | Final mass (g) | Mass change | Rust score | Notes |
|---|---|---|---|---|---|---|
| Control | 0 | |||||
| Cathode | ||||||
| Anode |
Observations & sketches: Note bubble formation, pitting, flaking — include photos numbered and referenced.
Analysis questions:
- How did corrosion differ between cathode/anode/control? Use data.
- Explain the chemical reactions at each electrode (oxidation/reduction equations).
- Was current stable? How might fluctuations affect the experiment?
Calculations: Show mass changes; consider rate (mass change per hour).
Conclusion & Evaluation: State whether electrical protection (cathodic protection) or electrolysis increased corrosion and justify.
Extension: Suggest a real‑world application (e.g., ship hull cathodic protection) and design a scaled test.
Summary: Two sentences linking experiment to broader ideas (electricity drives chemical change; direction matters).
ACARA v9 mapping (Experiment 2 — post):
- Use quantitative measurements of electrical and mass change; interpret using redox concepts; evaluate safety procedures for electrical experiments.
Teacher comment (Amy Chua cadence)
Good work shows numbers and balanced equations. If you only wrote ‘it rusted more,’ that is not analysis. Show the current logs, explain the half‑reactions, and state whether your data truly support cathodic protection or not. Be exact.
Extended rubric — Electricity vs Iron Post‑lab
| Criterion | Excellent (4) | Proficient (3) | Developing (2) | Beginning (1) |
|---|---|---|---|---|
| Data & instrumentation | Accurate current logs, masses, and observations | Mostly accurate with minor gaps | Data present but inconsistent | Insufficient or missing data |
| Chemical explanation | Correct half‑equations and explanation linking to data | Mostly correct with minor errors | Partial or incorrect explanation | No chemical reasoning |
| Evaluation | Detailed evaluation with clear improvements | Reasonable evaluation | Limited evaluation | No evaluation |
Experiment 3 — Lemon Battery (MEL Science: Chemistry & Electricity)
Worksheet 3A — Pre‑lab Cornell
Title: Lemon Battery — Can fruit produce a useful voltage?
Aim: Build a lemon battery and measure voltage/current; test factors that change the output (type of metal, lemon condition, series/parallel connections).
Background: A galvanic cell converts chemical energy to electrical energy by redox reactions between two different metals in an electrolyte (acidic lemon juice). Historical context: early battery experiments (link to Haskins for medieval precursors to electrochemistry ideas).
Hypothesis: E.g., ‘If copper and zinc are used then the voltage will be ~1 V per cell; changing the metal pair will change voltage because of different electrode potentials.’
Variables:
- Independent: metal pair, number of lemons in series/parallel
- Dependent: open-circuit voltage (V), short-circuit current (mA), ability to light LED
- Controlled: lemon size, insertion depth, connection method
Materials: lemons, copper coins/strip, zinc nail/galvanized nail, wires, LED or small buzzer, multimeter, knife (teacher use), safety goggles.
Safety: Use knife carefully (teacher demo). Do not short-circuit cells. Handle metals safely.
Method outline:
- Insert copper and zinc into a lemon ~2 cm apart. Measure voltage across the two metals.
- Record voltage; try connecting two lemons in series; measure again.
- Attempt to light an LED — record whether it lights and any brightness observations.
Cornell cues:
- Which metal pair gives highest voltage?
- How does series vs parallel affect voltage/current?
ACARA v9 mapping (Experiment 3)
- Understanding of galvanic cells and energy transformation (chemical to electrical).
- Inquiry skills: measuring voltage/current, testing variables, communicating results.
Teacher comment (Amy Chua cadence)
Simple concept, simple execution — but your measurements must be careful. Read the multimeter properly. If your LED fails, don’t guess why — test voltage and current and explain. Precision matters even with lemons.
Extended rubric — Lemon Battery Pre‑lab
| Criterion | Excellent (4) | Proficient (3) | Developing (2) | Beginning (1) |
|---|---|---|---|---|
| Hypothesis & rationale | Quantitative expectation with electrode rationale | Qualitative expectation with reasoning | Vague or incomplete | Missing |
| Procedure clarity | Clear, repeatable steps and safety | Mostly clear | Some ambiguity | Not usable |
| Variables | Identified and controlled | Mostly identified | Partial | Poor |
Worksheet 3B — Post‑lab Cornell
Data table:
| Test | Metals | Open-circuit V | Short-circuit I (mA) | LED lights (Y/N) | Notes |
|---|---|---|---|---|---|
| Single lemon | Copper/Zinc | ||||
| 2 lemons series | |||||
| Alternate metal |
Observations: Note brightness, voltage stability, any corrosion on electrodes.
Analysis questions:
- What is the typical voltage per lemon cell and how does it compare to theoretical electrode potentials?
- Why does series increase voltage but not current? Explain using circuit terms.
- How could you increase current to light a bigger LED?
Calculations: If you measured internal resistance, show calculation: r = (V_oc - V_load)/I_load.
Conclusion & Evaluation: State success, limitations (internal resistance, contact resistance), and at least two specific improvements or further tests.
Extension: Research Daniell cell (lead into Experiment 4) and compare expected voltages.
Summary: Short summary linking chemical potential difference to observed voltage.
ACARA v9 mapping (Experiment 3 — post):
- Measure and interpret voltage/current; link to redox potentials; evaluate experimental limitations like internal resistance.
Teacher comment (Amy Chua cadence)
Good experiments show both success and calculation. If your LED didn’t light, explain why with numbers — voltage and current. Weak answers that say ‘it didn’t work’ are not acceptable. Show your measurements and reasoning.
Extended rubric — Lemon Battery Post‑lab
| Criterion | Excellent (4) | Proficient (3) | Developing (2) | Beginning (1) |
|---|---|---|---|---|
| Data & interpretation | Complete measurements and clear interpretation with circuit concepts | Good measurements and interpretation | Some missing data or weak interpretation | Incomplete |
| Calculations | Correct internal resistance or predicted voltage calculations | Mostly correct | Errors present | None |
| Evaluation | Specific, practical improvements and next steps | Reasonable ideas | General or poor ideas | None |
Experiment 4 — Daniell (Daniel) Galvanic Cell (MEL Science: Chemistry & Electricity)
Worksheet 4A — Pre‑lab Cornell
Title: Daniell cell — Build and measure a classical galvanic cell.
Aim: Construct a Daniell cell (copper and zinc electrodes in their sulfate solutions separated by a salt bridge) and measure voltage; compare to lemon battery and discuss improvements.
Background: The Daniell cell is a historical galvanic cell producing stable voltage by combining two half‑cells; it reduces polarization and internal resistance compared to simple fruit cells.
Hypothesis: Predict the open‑circuit voltage and whether the Daniell cell gives a higher current than lemon cells.
Variables:
- Independent: electrode metals, concentration of solutions, salt bridge composition
- Dependent: voltage, current, stability over time
- Controlled: electrode surface area, temperature
Materials: copper electrode, zinc electrode, copper sulfate solution, zinc sulfate solution, salt bridge (agar + KCl or simple bridge), voltmeter, wires, beakers, safety equipment.
Safety: Handle chemicals and glassware with care; avoid spills; wear goggles and gloves.
Method outline:
- Set up each half cell in separate beakers connected by a salt bridge; connect electrodes to multimeter; measure open-circuit voltage and current under known load.
- Record voltage stability over time (e.g., every 5 minutes for 30 minutes).
Cornell cues:
- How does salt bridge composition affect voltage stability?
- How does concentration affect cell voltage?
ACARA v9 mapping (Experiment 4)
- Chemical understanding of redox, standard electrode potentials, and energy conversion in galvanic cells.
- Inquiry skills: controlled setup, measuring time‑dependent data, comparing historical (Daniell) vs simple cells.
Teacher comment (Amy Chua cadence)
Historical cells are elegant because they work reliably — your measurements should show that. Don’t rely on anecdote; produce a voltage‑over‑time graph, note the effect of salt bridge, and link to electrode potentials. Be rigorous.
Extended rubric — Daniell Cell Pre‑lab
| Criterion | Excellent (4) | Proficient (3) | Developing (2) | Beginning (1) |
|---|---|---|---|---|
| Preparation & setup | Detailed plan for two half‑cells and salt bridge | Plan present, minor omissions | Incomplete plan | Poor |
| Hypothesis & theoretical link | Predicted voltages with electrode potential references | Prediction with some theory | Vague | Missing |
Worksheet 4B — Post‑lab Cornell
Data & graph prompts:
- Table: Time (min) vs Voltage (V) under open circuit and under known load (e.g., 100 Ω)
- Plot voltage vs time (attach graph/photo)
Observations: Note bubble formation, electrode color changes, precipitate formation, salt bridge effects.
Analysis questions:
- Compare measured open‑circuit voltage to expected using standard electrode potentials. Explain differences.
- Explain how concentration cell effects or internal resistance could change voltage over time.
- Compare efficiency and practicality of Daniell vs lemon battery for small devices.
Calculations: If you measured internal resistance r: use V_load = V_oc * (R/(R + r)). Solve for r if V_load & R known.
Conclusion & Evaluation: Provide evidence‑based conclusion about Daniell cell performance and suggest two ways to improve output or stability.
Extension: Research how modern batteries evolved from cells like Daniell and link to real‑world uses.
Summary: Two sentences linking experiment to redox potentials and energy conversion.
ACARA v9 mapping (Experiment 4 — post):
- Use data to interpret cell potential against theoretical electrode potentials; evaluate experimental causes of deviations; connect historical development to modern batteries.
Teacher comment (Amy Chua cadence)
Show your graph. If you did not record time series, explain why and what you would do differently. Precise numbers and calculations prove understanding — not vague statements. I expect neat graphs, correct units, and reasoned conclusions.
Extended rubric — Daniell Cell Post‑lab
| Criterion | Excellent (4) | Proficient (3) | Developing (2) | Beginning (1) |
|---|---|---|---|---|
| Data & graphing | Clear table and correctly labelled graph showing trends | Good graph with minor labelling issues | Graph present but unclear | No graph |
| Theoretical comparison | Accurate comparison with standard potentials and reasoned explanation | Mostly accurate | Partial understanding | No theoretical link |
| Evaluation & improvements | Specific, practical improvements and discussion of uncertainties | Reasonable improvements | General ideas | None |
How to use these worksheets in class
- Print Worksheet A for students to complete before lab — ensures they plan properly and understand safety.
- Provide Worksheet B immediately after lab for completion while observations are fresh; require calculations and a two‑sentence summary.
- Use the rubrics to mark work and to give targeted feedback; the teacher comments model a high‑expectation voice — edit tone if you prefer a gentler style.
- Map assessments to ACARA v9 by identifying which strand and inquiry skill each criterion addresses; use the rubrics to report achievement against those strands.
If you would like, I can convert each worksheet into a printable single‑page PDF layout (two columns: left cue column, right note area) or editable Google Doc templates. Tell me which format you prefer and whether you want gentler teacher comments instead of the strict cadence.