PhET Interactive Simulations is not an AI tool. It is a free library of interactive science and math simulations run from the University of Colorado, and it earns a place in a toolbox because it does something chat assistants can't: it lets you see and change a system while it runs.

What it is

  • Free simulations for students and teachers, supported by sponsors such as the National Science Foundation and the Gordon and Betty Moore Foundation.
  • Subjects: physics, math and statistics, chemistry, earth and space, and biology.
  • Built in HTML5, so most simulations run straight in the browser. You can also download them, and there are iOS and Android apps.
  • Open source, with about 48 language options in the interface.
  • PhET says it tests each simulation with student interviews and classroom observation.

Why it's useful

Reading that a higher voltage pushes more current through a circuit is one thing. Dragging a battery slider and watching the current change is another. Each simulation is a small sandbox: you change a variable, the model responds immediately, and you notice the pattern yourself.

A few simulations worth trying first:

  • Circuit Construction Kit: DC, to build circuits and see how voltage, current, and resistance relate.
  • Projectile Motion, to change launch angle and speed and watch the path.
  • Build an Atom, to see how protons, neutrons, and electrons define an element.
  • pH Scale, to compare common liquids on the acidity scale.

Using it with AI tools

PhET and chat assistants cover different gaps. The simulation shows what happens; an assistant can explain why.

  • Run a simulation, write down what you observed in your own words, then ask ChatGPT or Claude to check your explanation and point out what you missed.
  • Ask for three "what if" questions to test in the simulation, then go and test them.
  • Teachers can ask an assistant to turn a simulation into a short worksheet, then adjust the questions to their class. Check the output yourself before handing it out.
  • Use NotebookLM to summarize a chapter, then use the matching simulation to test the ideas in it.

Who it's for

Students who want to build intuition before or after a lesson, teachers who need a quick classroom demo, and self-learners who find formulas easier once they have seen the behavior.

Limits

  • It covers science and math topics only, and not every topic has a simulation.
  • It teaches concepts, not exam technique, so pair it with practice problems.
  • Because it isn't an AI product, it won't answer your questions. That is where an assistant helps.

Open PhET to try it. It is free and needs no sign-up to run in the browser.

This entry is editorially independent and not influenced by ToolBid's sponsorship program.