PhET sims are amazing.
Without guidance, they're just toys.
Pengi sits inside every PhET simulation and turns random slider-moving into real scientific discovery — with voice guidance.
phet.colorado.edu/sims/gravity-force
Pengi Live TutorWhat happens to the force when you move the objects closer together?
The force gets bigger!
Right! That's the inverse-square law in action.
Sound familiar?
PhET sims are powerful. But without guidance, students just move sliders randomly.
"I moved the slider but nothing makes sense"
Changed mass in Gravity Force Lab but doesn't connect it to the formula.
Pengi:"You doubled the mass. Look at the force arrow — did it get bigger or smaller? What does that tell you about the relationship?"
"The bulb won't light up!"
Built a circuit in Circuit Construction Kit but left a gap or used wrong components.
Pengi:"Trace the path from the battery's + terminal. Does the current have a complete loop back to the − terminal?"
"How do I hit the target?"
Projectile Motion sim — trial-and-error without understanding angle vs velocity trade-off.
Pengi:"You're shooting at 80°. What happens to the horizontal distance if you lower the angle? Try 45° and watch."
"What am I supposed to learn from this?"
Teacher assigned a PhET sim but the student doesn't know what to observe or explore.
Pengi:"This sim shows wave interference. Try changing the frequency of one source. What happens where the two waves meet?"
4.2x
deeper concept retention
vs reading textbook alone
< 3 min
from confused to exploring
with guided questions
91%
complete their PhET lab
instead of random clicking
Without Pengi vs. with Pengi
Result: simulation = fancy toy, no learning
Result: simulation = real lab experience
From install to “aha!”
in 30 seconds
Install & sign in
30 seconds.Add the Pengi extension from the Chrome Web Store and sign in with Google or email.
Works on Chrome, Edge, Brave. Parents can create managed student accounts.
Open any PhET simulation
Pengi appears automatically.Go to phet.colorado.edu and open any HTML5 sim. A Pengi button appears in the top-right corner.
Pengi tracks slider changes, object positions, and simulation state in real time.
Explore with guidance
Voice or text."Why did the force change?" "What should I try next?" — Pengi sees what you're doing and responds.
Socratic method: guides discovery, never gives away the answer.
“But my kid has a
science teacher”
Great. Pengi is the lab assistant that's always available.
During lab assignments
Teacher assigns a PhET sim but can't sit with every student. Pengi fills that gap — asking the questions a good teacher would.
Connecting sim to theory
Students play with sliders but miss the physics. Pengi bridges the gap: "You changed X. What happened to Y? What law explains that?"
Building scientific thinking
Instead of "the answer is 9.8 m/s²", Pengi asks "what would happen on the Moon?" — teaching students to think like scientists.
Every PhET sim becomes a guided lab experiment —
not just a toy to click around in.
Common questions
- Does PhET have a built-in AI tutor?
- No. PhET simulations are standalone interactive tools with no built-in guidance. Pengi's Chrome Extension adds an AI tutor layer that activates automatically on any PhET sim and guides students through the exploration.
- How does Pengi know what my child is doing in the simulation?
- Pengi reads the simulation state in real time — slider positions, object locations, displayed values, and your child's interaction history. It uses this context to ask relevant guiding questions.
- Will the AI give away lab answers?
- Never. Pengi uses the Socratic method — "What happened when you doubled the mass?" "What does that tell you about the relationship?" Your child discovers the science themselves.
- Which PhET simulations does it support?
- All HTML5-based PhET simulations at phet.colorado.edu — Gravity Force Lab, Projectile Motion, Circuit Construction Kit, Wave Interference, and 100+ more.
- Is it free?
- The Chrome Extension is free to install and includes a free trial. After the trial, plans start at a few dollars per month — less than a single tutoring session.
- Does it work on other platforms?
- Yes. The same extension also works on Khan Academy, IXL, and Scratch — providing Socratic tutoring on each platform.
Turn every PhET sim
into a real lab experience.
No more random clicking. No more guessing worksheet answers. Pengi makes sure your child actually learns the science.
Free trial included. Works on PhET, Khan Academy, IXL, and Scratch.