Grid Lock

Each round gives you a latitude and longitude. Read the blank grid, drop your pin where you think the point lands, and lock it in. Accuracy across several rounds builds your score.

• Click the grid to place your pin at the target coordinate
• Lock the pin to score that round on how close you landed
• Optional hints (such as the hemisphere) cost points if bought
• Play through a set of rounds for a final total

• Desktop: click the grid to place the pin, then click Lock pin
• Phone & tablet: tap to place the pin and tap Lock

• Anchor yourself on the equator (0°) and prime meridian, then count outward
• Remember positive latitude is north and positive longitude is east
• Save hints for the rounds where you're genuinely lost, they eat your score

Grid Lock is a latitude-and-longitude precision game on a faint, label-free grid, building coordinate skills on a global map.

• Skills: latitude and longitude, coordinates, map grid, precision
• Best for: roughly grades 5–10 (ages 10–16)
• For parents & teachers: makes the global coordinate grid concrete.

Dropping a pin at a given latitude and longitude on a blank grid is the geographic coordinate system without the crutch of coastlines.

Removing the map is the original difficulty.

Coordinates are usually read off a map, which hides how unevenly they behave. A degree of latitude is a constant distance everywhere; a degree of longitude shrinks to nothing at the poles — so the same numeric error means very different things depending where you are.

Grid Lock is a latitude-and-longitude precision game on a faint, label-free map grid. It's an original, free browser game built in-house for PlayPendium.

A free, original browser game on PlayPendium. No download, no install.