Learn Science for Free With PhET Interactive Simulations
Interactive simulations help learners test what changes when a variable moves.
This guide focuses on decisions you can make with information you can check yourself. Work through the evidence in order, document anything that may change, and prefer the original provider or authority for current conditions. The goal is to make the next practical step easier, not to promise an outcome that depends on other people or services.
Find a simulation that matches a lesson
PhET from the University of Colorado Boulder offers free interactive simulations for science and mathematics. Browse by subject and check the recommended grade level. The availability of language versions and device controls varies by simulation.
Make one prediction before clicking
For a circuit simulation, predict how changing a component affects the result. For a motion model, write down what you expect when mass or force changes. This turns exploration into a small experiment rather than random clicking.
Change one factor at a time
Keep the other controls steady while adjusting one variable. Record the result using words, a table or a screenshot. A simulation illustrates a model, so remember that its assumptions may differ from real laboratory conditions.
Explain the result independently
After using the simulation, close it and explain why the result occurred. Return to a textbook or teacher’s notes if the explanation is unclear. For classrooms, combine the activity with a short written question.
Check accessibility and offline options
Some simulations are usable in several languages or through downloadable versions, but not every activity supports every device. Test before a lesson and have an alternative for pupils who cannot interact easily with the controls.
Worked example
Example: in a virtual circuit, predict what happens when a second bulb is added in series, then test it and explain the change. Record the arrangement and the simulated result rather than treating the animation as a replacement for electrical safety training.
Common mistake to avoid
A simulation is a model. Its simplified assumptions and interactions should not be mistaken for safe instructions for household electrical work.
Printable five-step checklist
Use these prompts as a short worksheet. Save the answers next to your own notes so you can repeat the process rather than relying on memory or a single screenshot.
Questions people ask
What should you verify first?
Begin with “find a simulation that matches a lesson.” Check the original evidence, then make the smallest reversible decision available. If the information is incomplete, record what remains unknown before making a commitment.
How can you avoid a common mistake?
A simulation is a model. Its simplified assumptions and interactions should not be mistaken for safe instructions for household electrical work. Retest the conclusion against the source links below, especially when pricing, eligibility, safety guidance or software functions may have changed.