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for green and red "Hint" and "Walkthrough" boxes!
**Choose Your Path:** Select one of the following investigation pathways
based on your interests: - **Path A:** [topic-specific content] - **Path
B:** [topic-specific content] - **Path C:** [topic-specific content]
**Specialist Track:** As you progress, you'll develop expertise in
[topic-specific content]. Advanced learners: try the extension challenge at
the bottom of this page.
**Career Connection:** [topic-specific content] scientists and engineers use
these skills daily in careers like [topic-specific content]. High school
[topic-specific content] builds on these concepts.
**You're in Control:** Design your own investigation to answer:
[topic-specific content]. Use the scientific method, but YOU decide the
procedure, materials, and data collection strategy.
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Week 4 - Cycle 1 Finale!
This is WEEK 4! You'll integrate all Cycle 1 concepts
(W1+W2+W3).
KEY CONCEPT: Energy breaks bonds during phase changes
(temp stays constant!)
Exit Ticket: Tests your understanding of ALL 4 weeks!
NGSS Standards
MS-PS1-4 (Primary)
Develop a model that predicts and describes changes in particle
motion, temperature, and state of a pure substance when thermal energy
is added or removed.
Phenomenon: The Shrinking Balloon Mystery
The experiment:
Balloon filled with air at
room temperature (20°C)
Place in freezer (-18°C) for 30 minutes
Result: Balloon shrinks significantly but doesn't
pop
Return to room temp: Balloon
returns to original size
What's happening to the air particles inside the balloon?
Why does a balloon shrink when you put it in the freezer?
Look at the simulation controls.
Before changing any variables, predict what will happen when
you adjust them. Write your prediction down.
👀 OBSERVE (while using the sim)
Change one variable at a time. Record what happens after each
change. Use the data journal to capture at least 3 trials.
💡 EXPLAIN (after collecting data)
Compare your observations with your prediction.
Use scientific vocabulary to explain the patterns you
found.
What surprised you? What confirmed your thinking?
Atom: The smallest unit of an element (like
oxygen, hydrogen, carbon)
Molecule: Two or more atoms bonded together
(like H₂O - water)
Example: Water (H₂O) = 2 hydrogen atoms + 1
oxygen atom
Key Vocabulary (English | Spanish)
English
Spanish
Pronunciation
Atom
Átomo
/ˈætəm/
Molecule
Molécula
/ˈmɑlɪˌkjul/
Proton
Protón
/ˈproʊˌtɑn/
Electron
Electrón
/ɪˈlɛkˌtrɑn/
Part A: Build a Water Molecule (MS-PS1-1)
Before we study phase changes, let's understand what water is made
of at the atomic level.
6-Step Instructions: Building H₂O
ASK: What atoms do I need for water? (Hint: H₂O
means 2 hydrogen + 1 oxygen)
PLAN: First build oxygen atom (8 protons, 8
neutrons, 8 electrons)
CREATE: Drag protons, neutrons, and electrons
to build oxygen
TEST: Check that simulation shows "Oxygen" when
complete
IMPROVE: Note: The simulation builds atoms, not
molecules. We'll use this knowledge to understand H₂O.
COMMUNICATE: Answer questions in the form about
atomic composition
Part B: PhET States of Matter + Heating Curves
The Big Mystery: When you heat ice at 0°C,
temperature stays at 0°C until ALL ice melts. Where does the energy
go? And do the H₂O molecules break apart?
Phase
Particle Behavior
What Happens to Energy
Solid
Vibrate in fixed positions
Increases vibration (raises temp)
Melting
Bonds breaking
Breaks bonds (temp constant!)
Liquid
Slide past each other
Increases motion (raises temp)
Boiling
Bonds breaking
Breaks ALL bonds (temp constant!)
Gas
Move freely, fast
Increases speed (raises temp)
🔍 WORKED EXAMPLE: Phase Change
Energy Analysis (Week 4 - Independent Work)
Week 4 independence: YOU complete all work with just the problem.
Apply everything from Weeks 1-3!
🎯 PROBLEM:
You have 50g of ice at -10°C. You add 25,000J of energy. The ice
warms to 0°C (uses 1,050J), melts completely (uses 16,700J), then
warms as liquid. How much does the final water temperature
increase above 0°C? (Specific heat of water = 4.18 J/g°C)
✏️ YOUR TURN - Solve Independently:
Use your knowledge from all 4 weeks:
Track energy: What's left after warming + melting?
Apply specific heat formula: Q = mcΔT
Solve for temperature change
Explain why most energy went to melting, not warming
💡 Week 4 Mastery:
You've built skills across 4 weeks—particle motion (W1), heat
transfer (W2), specific heat (W3), phase changes (W4). Now
integrate them!
Misconception Alert!
Temperature does NOT always increase when you add heat! During phase
changes, energy breaks bonds instead.
▼ Need help understanding heating curves? ▼
Pattern to Remember:
Sloped sections = temperature rising (energy → particle motion)
Mission: Understand How Pressure Affects Boiling/Melting
Real-World Examples:
Scenario
Pressure
Effect on Boiling Point
Mountain (high altitude)
Low (95°C)
Water boils at LOWER temp
Sea level
Normal (100°C)
Standard boiling point
Pressure cooker
High (120°C)
Water boils at HIGHER temp
Why? Higher pressure pushes particles together →
need MORE energy to escape as gas.
Sublimation: Solid → Gas (No Liquid!)
Dry ice (solid CO₂) sublimes at normal pressure because its phase
diagram shows no liquid phase exists at that pressure!
COMPLETE STATION 2 FORM
Includes spirals from W1 (particles) and W2 (heat transfer)
[EMBED G8.C1.W4 Station 2 Form Here]
Form ID: ________________
Station 3 - Design a Phase Change Application
25 Points | ~20 Minutes (Highest Value!)
Engineering Challenge: Cooling Vest OR Instant Cold Pack
Choose ONE Challenge:
COOLING VEST: Keep construction workers cool in
hot weather using phase change materials
INSTANT COLD PACK: Design a cold pack that
activates instantly for sports injuries (no refrigeration)
Key Concept:
Melting (solid→liquid) ABSORBS energy from surroundings = COOLING
effect!
Design Requirements:
Choose material with melting point near body/injury temp
Explain how melting provides cooling
Describe how to "recharge" the device
Identify trade-offs (cost, weight, duration)
🎯YOUR CHOICE: Select Your Engineering Approach
You have THREE phase change engineering approaches.
YOU choose which design philosophy resonates with YOU!
All three can earn full points—pick based on YOUR priorities.
🔬 Path A: Material Science
Optimization (Maximum Performance)
Research phase change materials (PCMs) with exact melting
points. Calculate heat of fusion needed. Design for longest
cooling duration possible. Most technical but highest
performance.
If you value scientific precision and optimal performance,
choose this path.
Use readily available materials (ice packs, paraffin wax).
Optimize for low cost, easy recharging, and durability. Design
for mass market.
If you value affordability, accessibility, and real-world
practicality, choose this path.
Design using non-toxic, biodegradable materials. Minimize energy
for recharging. Consider full life cycle impact. May sacrifice
some performance for sustainability.
If you value environmental responsibility and long-term
thinking, choose this path.
💡 Why This Matters:
Real product engineers face these exact trade-offs! High-tech
cooling vests use Path A for athletes, drugstore ice packs use
Path B for consumers, and eco-companies use Path C for
sustainability. Your choice reflects authentic engineering values!
COMPLETE STATION 3 FORM
[EMBED G8.C1.W4 Station 3 Form Here]
Form ID: ________________
Exit Ticket - Matter & Thermal Energy Integration
23 Points | ~15 Minutes
Show What You Learned (ALL 4 WEEKS!)
Question Types:
2 NEW - Phase changes, energy during transitions
2 SPIRAL - W2 heat transfer + W1/W3
particle/thermal concepts
This exit ticket integrates ALL concepts from Weeks 1-4. Show what
you've learned about matter and thermal energy!
COMPLETE EXIT TICKET
[EMBED G8.C1.W4 Exit Ticket Form Here]
Form ID: ________________
Week 4 Summary: Phase Changes
Phase Changes: Energy breaks bonds instead of
raising temperature (flat sections on heating curves)
Melting/Boiling: Absorb energy;
Freezing/Condensing: Release energy
Pressure Effect: Higher pressure = higher boiling
point (particles need more energy to escape)
Applications: Phase change materials provide
cooling by absorbing energy during melting
Real-World Application: Freeze-Drying Technology
Freeze-drying uses sublimation—solid to gas without liquid phase—to
preserve heat-sensitive medicines, vaccines, and food. Materials
freeze solid, then in a vacuum chamber, ice sublimes directly to
vapor. This gentle process prevents damage to heat-sensitive
compounds. Astronauts use freeze-dried food (lightweight,
long-lasting), hospitals preserve expensive antibiotics, COVID-19
vaccines enable global distribution. By controlling pressure and
temperature precisely, engineers harness sublimation for pristine
preservation.
Cycle 1 Complete! What You've Mastered:
Week
Topic
Key Concept
Week 1
Thermal Energy & Particles
Temperature = average KE; Thermal energy = total KE
Week 2
Heat Transfer
Conduction, convection, radiation
Week 3
Thermal Properties
Specific heat, conductivity, material selection
Week 4
Phase Changes
Energy breaks bonds during phase transitions
👇🌟 Enrichment & Extension
👇 Optional deep dives for early finishers.
Optional content if you finish early or want to go deeper.
👨🔬 Scientist Spotlight
Research a scientist who contributed to this week's topic area and
describe their key findings.
⚖️ Environmental Justice Connection
Explore how this week's science concepts connect to environmental
justice issues in our community.