The challenge mode is a simple game mode returning from previous FIFA versions. The FIFA 08 version is said to be much more difficult than previous ones. The general concept is that you have ten regions to play in, each with ten challenges to complete, except for Region 1, which features 15 challenges to complete, so 105 challenges in total. The incentive to do challenge mode other than for entertainment is that you can accumulate points by completing challenges which can be used to unlock things like balls and kits for use in other game modes of FIFA 08.
When you begin Challenge Mode in FIFA 08, you will have one of the ten challenges unlocked in each region, except for Region 1, which has two unlocked challenges at the start. Your first challenge will be easy, but don't be fooled, they get very difficult as you advance. As you complete challenges, the next ones will be unlocked for you to continue. Region 10 is locked at the start, so you will need to complete the other regions before you can begin 10. Challenge objectives examples include: Score a goal with a midfielder, Achieve 50% passing success, Keep a clean sheet, and an endless list of others. As you beat more challenges, they will get harder by including objectives which are very hard to achieve together like scoring two goals while also keeping 100% of your shots on target.
As you complete challenges, you will be rewarded with points which you can use in the Fan Shop. To get to the Fan Shop: Main Menu - My FIFA 08 - EA Sports Extras - Fan Shop. In the Fan Shop, you can buy the third kits of certain clubs which are locked by default until you buy. You can also buy footballs to use in games and boots to unlock for your favorite player to wear. The last thing you can buy is experience points, which can be spent to boost the attributes of either the current arena player, or used in the creation zone on your created player.