A+ Click is a free site full of online mathematics games for students at all grade levels. You can find games on A+ Click by selecting a grade level then selecting a topic. Alternatively, you select just a topic or just a grade level and browse through all of the games. Students do not need to register in order to play the games.
This would be a great IWB morning starter as the children walk into the room. They could silently read through as you are doing the roll and lunch orders. One child could be the controller.