Science
Domain 4: Science
The OSAT Elementary Education Science domain tests scientific inquiry, life science, Earth and space science, and physical science. Candidates must interpret investigations, identify variables, use evidence to support claims, and explain core concepts at a level suitable for elementary learners.
Core rules and concepts
- A fair test changes one independent variable, measures one dependent variable, and holds controlled variables constant.
- Observations are gathered through the senses or instruments; inferences are explanations based on observations and prior knowledge.
- Mass is the amount of matter; weight is the force of gravity on that mass. Density is mass per unit volume.
- In a food chain, arrows show the direction of energy flow. Producers capture sunlight; consumers obtain energy by eating other organisms.
- Earth’s rotation on its axis causes day and night; revolution around the Sun, combined with axial tilt, causes seasons.
- In a series circuit, there is one path for current; in a parallel circuit, there are multiple paths.
Worked example
A rock has a mass of 24 g. When placed in a graduated cylinder, the water level rises from 30 mL to 38 mL. The rock’s volume is 8 cm³, because 1 mL equals 1 cm³. Density equals mass divided by volume: 24 g ÷ 8 cm³ = 3 g/cm³. Since 3 g/cm³ is greater than the density of water (about 1 g/cm³), the rock sinks. Reasoning: use displacement for irregular volume, keep units consistent, and compare density to predict floating or sinking.
Traps that cost marks
Do not confuse mass and weight. Do not label an inference as an observation. Do not reverse rotation and revolution. Do not say food-chain arrows show “who eats whom” without noting energy flow. Do not confuse series and parallel circuits.