Terra Geometrika
Build floating islands with the ruler, the set square and the compass
A block-world adventure game for learning geometry in grades 4-5: on a sheet of vellum the student draws real plans with a graduated ruler, a set square and a compass, then watches them turn into bridges, gates, bastions and cities. A kind error detector shows the measured gap instead of punishing. A free island, "My island", turns the drawn shapes into buildings, and a dashboard lets the teacher follow the class.
Audience : Students in grades 4-5, families and teachersLevel : Grades 4 – 5 (ages 9-11)
Sign in to use Terra Geometrika
Sign in with your e-mail address or with Google. The app then opens in your browser.
What the app does
- Four adventure chapters: parallels, perpendiculars and midpoints, triangles, quadrilaterals (rectangle, rhombus, square).
- A precision workshop: pencil, dry point, graduated ruler, set square that locks at 90°, compass, eraser, undo, help.
- Exact validation to the millimetre and the degree, with three tolerance levels (soft, normal, precise).
- A kind error detector: ghost of the right line, gap gauge, Mentor bubble, never a failure screen.
- Stars and crystals according to precision, three outfits for the avatar, plans materialised in blocks.
- "My island": a free plan whose recognised shapes (circle, triangle, rectangle, square, rhombus) become buildings, with a code to visit a classmate's island.
- Teacher dashboard: progress by chapter and by notion, pupils in difficulty, frequent errors, CSV export, pseudonyms only.
- Interface in French, English and Indonesian; dyslexia-friendly font; first-launch tutorial.
How it works
- 1Read the missionThe Mentor presents the context and the construction programme.
- 2DrawBuild the plan on the vellum with the ruler, the set square and the compass.
- 3CheckThe error detector shows the measured gap and helps to correct it.
- 4BuildThe successful plan turns into blocks: stars, crystals and new buildings.
Why it is useful
- Instrument geometry becomes concrete: students really draw, with real tools.
- A mistake is information (a gap in mm or degrees), not a failure.
- Guided progression from the line to the square, with rewards that encourage precision.
- The teacher follows the class without ever handling a pupil's name.
Good to know
- This game uses no artificial intelligence: it uses no credit.
- Progress, settings and the island stay in the device's browser; nothing is sent anywhere.
- Class tracking works with tracking codes that pupils give to the teacher: only pseudonyms ("Pupil 1") appear.
- Designed for tablets (finger), it also works with a mouse; it opens in the browser, with nothing to install.