Physical Science

Fifth grade physical science boils down to one big question: what is stuff made of, and what happens when you change it? The 5-PS1 standards ask kids to understand matter at the particle level — why ice melts, why salt dissolves, why burning wood isn’t the same as cutting wood, and why a sealed bag of baking soda and vinegar weighs the same after the reaction as before.

These aren’t trivial ideas. Conservation of matter is genuinely counterintuitive. When a puddle disappears, it really does look like water was destroyed. When wood burns, the ash clearly weighs less. Kids need to wrestle with these apparent contradictions and come out understanding that matter is never created or destroyed — it just changes form.

Properties and Particles (Weeks 1-2)

Week 1 covers the properties of matter — the observable and measurable characteristics scientists use to describe and identify materials. Color, hardness, magnetism, solubility, density, conductivity. The focus is on using properties systematically, not just listing them: if an unknown metal is silver, non-magnetic, and has a density of 2.7 g/cm³, you can identify it as aluminum.

Week 2 introduces the particle model. Everything is made of particles too small to see. In solids, they vibrate in place. In liquids, they slide past each other. In gases, they fly freely. This model explains why solids have definite shapes, liquids take the shape of their container, and gases fill any space. It’s abstract, but it explains everything that follows.

Mixtures and Changes (Weeks 3-6)

Week 3 covers mixtures and solutions — how substances combine without creating new substances, and how they can be separated back out using filtration, evaporation, and magnetism. Week 4 introduces changes of state: melting, freezing, evaporation, condensation, and sublimation, all explained through the particle model.

Week 5 is conservation of matter — the idea that mass doesn’t change regardless of what you do to it. Dissolve salt? Same total mass. Melt ice? Same mass. Burn wood in a sealed container? Same mass. This is one of those foundational principles that shows up in every science class going forward.

Week 6 draws the critical line between physical and chemical changes. Cutting, melting, and dissolving are physical — the substance is still the same. Burning, rusting, and cooking are chemical — new substances form with entirely different properties.

Applications (Weeks 7-9)

Week 7 puts it all together with identification challenges — using multiple properties to figure out what an unknown substance is, the way real scientists and engineers work. Week 8 connects everything to the real world: kitchen chemistry, weather science, environmental issues, and engineering design. Why does bread rise? Why does a puddle dry faster in the wind? Why can aluminum be recycled forever but paper can’t?

Week 9 is a full cumulative review. Each week has 5 worksheets with complete answer keys and reading passages that explain the science before students practice applying it.