Grandparents of tweens are always challenged to come up with birthday gifts. This one is not only awesome it can be free. Kids get to put the pedal to the metal for nothing on their birthdays at Gokart Racing in Burlingmame. The only other requirement is that they are 12 and at least 4’10”.Up the road in Redwood City Malibu Grand Prix is offering a birthday package with 500 free tickets. It’s a larger, much more elaborate venue. Once at either location, you’ll be sorely tempted not to hop in one yourself.