So I'm teaching Distance/Speed/Time to my new S3 class, and I decided to look for some slightly more imaginative starters, as you do. A quick hunt round t'internet brought up Usain Bolt's world record time of 9.58 seconds for the 100m, set in Berlin in 2009. It's a nice enough question to ask the class to work out Bolt's speed in kilometres per hour, but an even better one is: should he have been arrested for speeding? It seems that in residential areas in Germany there's often a speed limit of 30kph.
There's even a clip you can show from youtube (along with annoying adverts, for which apologies):
See what your class think. I won't spoil things by telling you the answer.