Here's an example of one of my favourites:
Design a game
Design a game that can only be played in this place.
GeographyThink carefully about the objects, patterns and other things you can use to help you make up your game.
Mission number: ME1154
TipsTry to design a game that doesn't involve a lot of shouty stuff or throwing spiky objects.
Cool huh? Clearly I am a big fan of getting kids noticing and doing and engaging so when cool geographer Dan from The Geography Collective tweeted that my brown signs idea would make a good mission for Mission: Explore I jumped at the chance to write one for them, and they liked it!
It has just been added to the site and is here if you would like to have a look... Go Brown Sign Collecting! and even better accept the mission and do it yourself or with your kids, and be sure to tell me how you're getting on!