110304-F-LX971-077ANSWER: They all have recently taken up the sport of Aussie Rules Football (or "footy" as we affectionately refer to it).

See the photos from the Australian Prime Minister's recent visit to the Oval Office where she taught President Obama some hand passing and kicking:

Photos of Gillard's visit with Obama

Actually, Karl and Dane are no longer "new" to the game of footy.  They've been playing it at home and school for nearly 3 years.  Dane, in particular, was on a long run of playing it nearly every recess and lunch.  However, for the first time Karl and Dane have registered to play for our local footy club - the Warnbro Swans.  Training has just started as the season will run now through autumn and winter.