ModelDuel
Education · Moon phases

Evidence-led science learning

Two models predict.Evidence decides.

Pit the common claim that Earth's shadow causes Moon phases against the sunlight-and-viewing-angle model, then run both worlds under one sealed test.

The learner model claims Earth’s shadow causes Moon phases. The scientific model uses sunlight and viewing angle. The shared half-lit Moon observation has no Earth-shadow intersection, so the scientific model explains the evidence.

Model comparisonPreparing 3D view
Two proposed models will meet one shared observation.The complete comparison remains available without WebGL.
  • Evidence stays hidden until you commit.
  • Physical observation stays separate from model claims.
  • Your final transfer result is checked only by the server.
Choose a science challenge

Verified experiment · step 1 of 7

What causes the Moon's phases?

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Live GPT is only for people 18 or older, or learners using it with teacher or guardian authorization. Do not enter a student’s name or any personal or identifying information. For replay safety, ModelDuel schedules normalized live revision feedback for deletion after the authorization window and a one-minute grace. It attempts to re-arm cleanup after storage failures; its replay ledger does not store the raw revised explanation. The verified sample is open to everyone, sends no learner input to GPT, and requires no confirmation.

Live analysis uses your submitted text and optional sketch. The verified sample is an authored, API-free path and never claims to analyze your input.