Coordinate Castle is a free first-person 3D game for KS1 and KS2. Children explore a blocky castle and hunt for hidden treasure by reading grid references, (x, y) coordinates and compass directions on a mini-map, walking to the correct square and digging. Because the treasure is invisible in the 3D view, the only way to find it is to read the coordinates. It builds map skills, coordinates, compass points and following routes. No login, nothing uploaded, works on Chromebooks.