Physical Science: Matter, Energy, and Interactions

This is the foundation for the entire year: matter is made of atoms and molecules in constant motion, and that one idea explains why solids hold their shape, why gases spread out, what temperature actually is, and what happens during melting or evaporation. It starts with heavily worked examples and diagrams, then gradually asks your child to draw and explain things on their own.

1. Atoms and molecules build everything+

   Students state that all matter, living and nonliving, is composed of atoms and that molecules are combinations of bonded atoms.

2. Drawing particles in three states+

   Students draw and label a particle diagram for a given state of matter (solid, liquid, or gas), showing correct relative spacing and motion.

3. Particles and how matter behaves+

   Students explain why a solid keeps its shape while a gas fills any container, connecting the observable behavior to particle spacing and motion.

4. Calculating density and particle spacing+

   Students calculate density from mass and volume and predict relative density from a particle-spacing diagram before calculating.

5. Using density to tell substances apart+

   Students use measured density data to argue whether two visually identical unknown substances are the same material, citing evidence.

6. Temperature and particle motion+

   Students explain temperature as a measure of average particle motion rather than a fixed property of a substance.

7. Particle count during phase changes+

   Students model a phase change (melting, freezing, evaporation, or condensation) showing that particle count is conserved while arrangement and spacing change.

8. Particle count in new phase changes+

   Students apply the conservation-of-particle-count idea to a phase change not drilled in class (e.g., sublimation of dry ice, condensation on a cold glass), showing the belief transfers beyond the practiced case.

9. Phase change versus chemical change+

   Students distinguish evaporation of a substance from a chemical change into a new substance, rejecting the 'turned into a different gas' explanation.

10. The particle model in unfamiliar materials+

    Students predict and justify the particle-level behavior of an unfamiliar state or material never discussed in class, using taught spacing/motion rules.

11. Explaining a real phase change+

    Students write a claim-evidence-reasoning explanation connecting particle spacing, motion, and conservation for a self-selected real-world phase-change scenario not directly modeled.

12. Using text evidence about phase change+

    Students cite specific textual evidence from an informational science text to support a claim about particle behavior during a phase change.

Chemical reactions rearrange atoms into new substances, but they don't create or destroy them — so in a sealed system, total mass doesn't change even when a reaction is clearly happening. This is the same particle idea from Unit 1, now applied to reactions instead of states of matter.

1. Following atoms through a reaction+

   Given a labeled particle diagram of reactants and products, students identify which colored circles (atoms) appear in both, showing no atom is added or removed.

2. Closed and open systems+

   Students state the definition of a closed system versus an open system using their own example of each.

3. Spotting chemical and physical changes+

   Students classify a list of observed changes (color change, gas bubbles, dissolving, melting, precipitate forming) as evidence of chemical change or evidence of physical change.

4. Mass in open and closed systems+

   Students explain why the measured mass of an open-cup baking soda and vinegar reaction decreases while the same reaction in a sealed bag shows no measured change.

5. Predicting mass in a sealed reaction+

   Students predict the total mass reading of an unfamiliar closed-system reaction (e.g., an Alka-Seltzer tablet dissolving in a sealed bottle) before it occurs, and justify the prediction using atom conservation.

6. Slow and fast chemical changes+

   Students compare a rusting nail (slow reaction) and a burning match (fast reaction) to identify which features both share as evidence of chemical change.

7. Word equations and atom tallies+

   Students write a conceptual word equation for a given reaction (reactants arrow products) and check that every atom type is represented in both reactants and products using a tally.

8. Exothermic or endothermic from an article+

   Given an unfamiliar reaction description in a short science news article, students determine whether it is exothermic or endothermic using textual evidence about temperature change.

9. Testing an everyday chemical change+

   Students design a testable procedure to determine whether an everyday phenomenon not discussed in class (e.g., a glow stick, a rusting bike chain, dough rising) involves a chemical change, and predict what mass evidence would support their claim.

10. Why atoms are not destroyed+

    Students critique a peer's claim that 'the mass disappeared because the reaction destroyed some atoms,' identifying the specific reasoning error.

This unit builds Newton's three laws starting from something concrete — comparing how objects move on ice versus carpet — before naming any law or introducing any formula. It ends with your child diagramming forces and calculating acceleration using F=ma for situations they haven't seen before.

1. Balanced and unbalanced forces+

   Given a diagram of an object on ice and one on carpet, students identify which forces are present and classify each pair of forces as balanced or unbalanced.

2. Newton's first law and friction+

   Students state Newton's first law and use it to explain why a rolling ball on ice travels farther than one on carpet.

3. Calculating net force in one direction+

   Given force magnitudes and directions on a diagram, students calculate net force for two-and three-force scenarios along a single axis.

4. Solving F=ma for mass or acceleration+

   Students rearrange F=ma algebraically to solve for mass or acceleration when force and one other variable are given, in unfamiliar numeric contexts.

5. Using Newton's second law on new situations+

   Given a real-world scenario not covered in class (e.g. a person on a moving airport walkway, a skateboarder on a hill), students predict acceleration direction and magnitude trend using F=ma reasoning without being told which law applies.

6. Newton's third law in different situations+

   Students compare two interaction-pair scenarios (a swimmer pushing off a wall; a rocket expelling exhaust) and identify the shared structure of Newton's third law across both.

7. Drawing the partner force+

   Given a labeled diagram of one force on an object, students generate the correct interaction-pair force: same magnitude, opposite direction, acting on the other object.

8. Spotting errors in force diagrams+

   Students critique a flawed force diagram (with a missing normal force or a misdirected friction arrow) and identify what physical reasoning error produced it.

9. Designing with Newton's three laws+

   Given a completely novel design problem (a cargo container that must not slide during truck braking), students generate and justify a force-based design constraint using all three laws together.

Energy shows up in different forms — motion, height, heat, stretch — and moves between them, but the total amount in a closed system never actually goes away, even when it becomes harder to use (like spreading out as heat). This unit builds from spotting energy forms, to calculating kinetic and potential energy, to work as force times distance, to heat and efficiency.

1. Identifying forms of energy+

   Classify a described situation (falling rock, stretched rubber band, moving car, hot coffee) by which energy form(s) are present.

2. Kinetic energy and why speed matters+

   Calculate kinetic energy using KE = 1/2 m v^2 given mass and speed, and explain why doubling speed quadruples KE while doubling mass only doubles it.

3. Exponents and the shape of graphs+

   Compare two graphs of KE vs. mass and KE vs. speed for the same object and explain why one is linear and the other is not, connecting the shape to the exponent in the formula.

4. Work as force times distance+

   Determine work done on an object given force and distance, and judge whether work was done in a scenario where force is applied but no displacement occurs (e.g., pushing on a locked door).

5. Why heat flows hot to cold+

   Explain, using a particle-motion account, why heat always flows from a warmer object to a cooler one until thermal equilibrium, not the reverse.

6. Conserving energy in new systems+

   Given a novel closed-system scenario never discussed in class (e.g., a wind-up toy running down, a meteor burning up on entry), generate an energy-transformation account that conserves total energy and identifies where energy disperses.

7. Does a bouncing ball lose energy+

   Critique a claim that a bouncing ball 'loses energy' each bounce by identifying what actually happens to the energy, using evidence from a ball-drop investigation the student did not conduct.

8. Calculating efficiency as a percentage+

   Calculate the efficiency of an energy-conversion device (e.g., a lightbulb or a toy motor) as useful energy output over total energy input, expressed as a percentage.

9. Where energy disperses on a roller coaster+

   Design and justify a claim, supported by data from their own roller-coaster energy lab, about which section of the track had the greatest energy dispersal to thermal energy, then apply this reasoning to predict the outcome for a track design they did not test.

Waves move energy from place to place without moving the matter itself very far — a cork bobs up and down as a water wave passes but doesn't travel with it. This unit builds that idea with ropes and slinkies, and introduces amplitude, wavelength, frequency, and the wave speed formula v = fλ.

1. Reading amplitude and wavelength+

   Given a labeled transverse wave diagram, students identify amplitude and wavelength by pointing to the correct features.

2. Frequency and hertz+

   Students recall the definition of frequency as the number of wave cycles per second, in hertz.

3. Why mechanical waves need a medium+

   Students explain why a mechanical wave requires a medium, using the particle model of matter from Unit 1.

4. Longitudinal and transverse waves+

   Students classify a given wave demonstration (slinky push-pull vs. rope shake) as longitudinal or transverse based on the direction of particle motion relative to wave travel.

5. Calculating wave speed with v=fλ+

   Students calculate wave speed given frequency and wavelength using v=fλ, substituting correct units.

6. Particle motion versus energy transfer+

   Students compare a floating cork's motion to the wave's apparent forward motion, distinguishing particle oscillation from energy transfer.

7. When two wave pulses meet+

   Students predict what happens when two wave pulses traveling toward each other on the same rope meet, and justify the prediction using particle motion.

8. Why waves reflect at boundaries+

   Students construct an explanation for why a wave reflects at a boundary between two different media, applying the particle model.

9. Wavelength when a wave changes media+

   Given a novel scenario (a wave crossing from a fast to a slow medium at constant frequency), students infer what must happen to wavelength, with no worked example provided.

10. Common errors measuring wave diagrams+

    Students critique a peer's wave diagram labeling for a specific, named error (e.g., measuring amplitude crest-to-trough instead of crest-to-rest).

Sound is the hands-on, testable example of the wave ideas from Unit 5. This unit gets your child to actually measure frequency and amplitude from real sound traces, and pins down the difference between pitch (frequency) and loudness (amplitude), which kids very often mix up.

1. Wavelength and amplitude on a diagram+

   Given a labeled waveform diagram, identify which distance represents wavelength and which represents amplitude.

2. Calculating frequency from cycles and time+

   Calculate the frequency of a sound wave in hertz given the number of cycles and elapsed time, using the formula frequency = cycles / time.

3. Why sound cannot travel in a vacuum+

   Explain why a sound wave cannot travel through a vacuum, using the particle-collision mechanism of a longitudinal wave.

4. Pitch and loudness are separate+

   Given two waveform traces differing in either frequency or amplitude (not labeled), determine independently which trace has higher pitch and which is louder, citing the specific wave feature that supports each claim.

5. Why the same note sounds different+

   Compare the waveform of the same musical note played on two different instruments and explain why the note sounds different despite matching pitch and loudness.

6. Resonance and natural frequency+

   Predict which of several described objects (a wine glass, a bridge, a swing) is most likely to resonate at a driving frequency, and justify the prediction using the concept of natural frequency.

7. Design a test for frequency versus medium+

   Design a controlled test to determine whether an observed pitch difference between two mystery sound sources is caused by a difference in frequency or a difference in medium, using only measurement tools available in class.

8. How sonar uses reflected sound+

   Read a short technical passage on how sonar or ultrasound imaging uses reflected sound waves, and summarize the sequence of energy transformations described.

After two units establishing that mechanical waves need a medium, this unit opens with the twist: light doesn't. It moves from that core contrast through the electromagnetic spectrum, then into how light reflects and refracts at boundaries, and finally into why a prism splits white light into colors it was already carrying.

1. Light and sound in a vacuum+

   Students will state that light can cross a vacuum while sound cannot, citing the vacuum bell jar demonstration as evidence.

2. Electromagnetic and mechanical waves+

   Students will classify a given wave (radio, X-ray, sound, water wave, seismic wave) as electromagnetic or mechanical based on whether it needs a medium.

3. The law of reflection+

   Students will construct a ray diagram showing the angle of incidence equal to the angle of reflection for a given light ray and mirror.

4. Bouncing versus bending light+

   Students will compare a light ray reflecting off a mirror to a light ray refracting into water and describe what differs between the two cases before the rule is named.

5. Predicting which way light bends+

   Students will predict the direction a light ray bends when moving between two media of stated relative speed, and justify the prediction using the speed-change cause.

6. How a prism separates white light+

   Students will explain, using the two-prism recombination evidence, that a prism separates wavelengths already present in white light rather than creating color.

7. Light and sound at a boundary+

   Students will justify, for a novel scenario not used in instruction, why light crosses a medium boundary differently than sound does, connecting the medium-free mechanism to the boundary behavior.

8. Testing whether a wave needs a medium+

   Students will design a test, using only classroom materials, that would distinguish whether an unknown wave requires a medium to travel.

9. Wavelength and frequency across the spectrum+

   Students will order seven electromagnetic wave types by wavelength and relate wavelength to frequency across the spectrum.

The year closes by applying the particle model one more time — to charge instead of mass or energy. Students move from static charge to building circuits to magnetism, always tracking what happens to charge (moves, never created or destroyed) the same way they tracked mass and energy earlier in the year.

1. Charge transfer and static electricity+

   Explain a static electricity observation (comb and paper) using charge transfer between objects.

2. Conservation of charge+

   State that charge is conserved: it moves between objects but is never created or destroyed.

3. Current versus voltage+

   Distinguish current and voltage using the water-flow analogy in a labeled circuit diagram.

4. Building a closed series circuit+

   Diagram a closed series circuit that lights a bulb, given a battery, wire, and switch.

5. Series and parallel current paths+

   Predict which bulbs stay lit when one bulb fails in a given series or parallel circuit, by tracing current paths.

6. Forces that act without touching+

   Compare magnetic force and static electric force as two examples of non-contact force.

7. Current creating a magnetic field+

   Explain why running current through a coiled wire produces a magnetic field, using the particle model of current.

8. Designing a new electromagnet device+

   Design a novel device (not shown in class) that uses an electromagnet to solve a stated problem, and justify the design using current and field concepts.

9. Current path and voltage difference in an unfamiliar real-world scenario+

   Explain an unfamiliar electrical safety scenario (e.g., why a bird can sit on a power line unharmed) using the current-path and voltage-difference model.

10. Build, predict, and explain circuits+

    Build and diagram a working closed circuit, predict the effect of a stated circuit change, and explain a static electricity observation, integrating all unit models.