When not away travelling, I have been getting home early and taking the boys out bike-riding after school (and on the weekends, too). We sit together and plan our course (the more exotic the better, particularly if we can find a forest track to belt along) and set off. There is only one pre-requisite - we must stop at one of the local ice-cream shops on the way home!
Alexander is fairly accomplished and can handle his bike on most (normal) terrain now. Cameron has learned really well, and after a scare last weekend (had to pluck him off his bike as he raced by down a hill out of control) he is finally understanding the need for braking. He has since been more cautious, and is now getting the idea of using the brakes to stop (rather than running into expensive cars, for example!).
Cameron likes to push the boundaries, and has come up with a few beauties like "Look, I can ride with my eyes closed" - you have your heart in your mouth enough as they get the hang of riding a bike, but this added 'excitement' is not really necessary.
We have lots of fun, and it is great for us to get out into the nice weather and spend lots of time together.