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 as the building blocks of all matter+

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

2. Particle arrangement and motion in solids, liquids, and gases+

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

3. The relationship between particle spacing/motion and macroscopic state behavior+

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

4. Density as mass per unit volume, linked to particle spacing+

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

5. Density as evidence for distinguishing substances that look alike+

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

6. Temperature as average particle kinetic motion+

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

7. Conservation of particle number during phase change+

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

8. Conservation of particle number applied to an untaught phase-change context+

   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. The distinction between phase change and chemical change at the particle level+

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

10. Generalization of the particle model to untaught states of matter+

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

11. Synthesis of particle spacing, motion, and conservation to explain a novel scenario+

    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. Textual evidence supporting a scientific claim 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. Persistence of individual atoms across a chemical reaction, shown in particle diagrams+

   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. The distinction between closed and open systems+

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

3. Evidence that distinguishes chemical change from physical change+

   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. Conservation of mass in closed versus open systems during a gas-producing reaction+

   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. Conservation of mass applied to a novel closed-system reaction not used in instruction+

   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. Shared evidence of chemical change across reactions occurring at very different rates+

   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. Conceptual word-equation representation of chemical reactions with atom tallying+

   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 versus endothermic classification from textual evidence in an unfamiliar source+

   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. A novel everyday phenomenon evaluated for chemical change and mass-conservation evidence, using no in-class example+

   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. The error in claiming atoms are destroyed to explain apparent mass loss+

    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 vs. unbalanced forces on a moving object+

   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 (inertia) and its relation to 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. Net force calculation from multiple force vectors on one axis+

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

4. The F=ma relationship among force, mass, and 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. Application of Newton's second law to an unfamiliar mechanical context+

   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 as a general structure across dissimilar contexts+

   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. Construction of an interaction pair from a single given 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. Validity of a free-body diagram against the physical scenario it represents+

   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. Synthesis of Newton's three laws into one design justification+

   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. Kinetic, gravitational potential, elastic potential, and thermal energy forms+

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

2. The kinetic energy equation and its non-linear dependence on speed+

   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. The relationship between an equation's exponent structure and its graphical shape+

   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 multiplied by distance in the direction of force+

   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. Heat transfer direction and thermal equilibrium at the particle level+

   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. Conservation of total energy across transformations in an unfamiliar closed system+

   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. Energy dispersal versus energy destruction in a bouncing-ball system+

   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. Efficiency as a ratio of useful output energy to total input energy+

   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. Energy dispersal patterns across sections of a mechanical energy system+

   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. Amplitude and wavelength as features of a transverse wave diagram+

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

2. The definition and unit of frequency+

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

3. The causal link between particle-to-particle collision and mechanical wave propagation+

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

4. The distinction between longitudinal and transverse particle motion+

   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. The wave speed relationship v=fλ+

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

6. The difference between particle oscillation and net energy transport in a wave+

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

7. Superposition of two wave pulses on a shared medium+

   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. Reflection of a mechanical wave at a media boundary+

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

9. The relationship among wave speed, frequency, and wavelength across a medium change+

   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 in measuring amplitude and wavelength on a diagram+

    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 as distinct measured features of a wave diagram+

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

2. The frequency formula applied to counted wave cycles over a measured time interval+

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

3. The causal mechanism by which sound requires a medium of particles to compress and rarefy+

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

4. The independence of pitch (mapped to frequency) and loudness (mapped to amplitude) as separate wave properties+

   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. Timbre as the additional wave complexity (overlapping frequencies) beyond the fundamental frequency and amplitude+

   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 as a match between a driving frequency and an object's 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. An original experimental design isolating frequency as a variable independent of medium, for unfamiliar sound sources+

   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. The sequence of wave emission, reflection, and detection described in a technical text about sonar/ultrasound+

   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. The medium requirement difference between light and sound waves+

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

2. The mechanism distinguishing electromagnetic waves from 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 (angle of incidence equals angle 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. The structural difference between reflection and refraction at a boundary+

   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. The causal relationship between medium speed change and the direction of light bending+

   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. The wavelength-based explanation of prism dispersion+

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

7. The causal link between a wave's medium requirement and its behavior 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. An experimental method for detecting a wave's medium dependence+

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

9. The inverse relationship between wavelength and frequency across the electromagnetic 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 as the cause of 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. The distinction between current and voltage+

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

4. A closed series circuit+

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

5. Current paths in series versus parallel circuits+

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

6. Non-contact force, comparing magnetism and static electricity+

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

7. Electromagnetism: current producing a magnetic field+

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

8. Electromagnet applications in an unfamiliar device context+

   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. The integrated circuit-and-static-electricity performance task+

    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.