5-PS1-1 - Develop a model to describe that matter is made of particles too small to be seen.

Clarification Statement - Examples of evidence could include adding air to expand a basketball, compressing air in a syringe, dissolving sugar in water, and evaporating salt water.

Assessment Boundary - Assessment does not include the atomic-scale mechanism of evaporation and condensation or defining the unseen particles.

5-PS1-1 - Use a particle model of matter to explain common phenomena involving gases, and phase changes between gas and liquid and between liquid and solid.

Clarification Statement - Examples of common phenomena the model should be able to describe include adding air to expand a balloon, compressing air in a syringe, and evaporating water from a salt water solution.

Assessment Boundary - Atomic-scale mechanisms of evaporation and condensation or defining unseen particles are not expected in state assessment.