Pretty good entry to the contest
It lacked variety, but made up for it in the "see how many you can volley" factor. And the AI of your partner wasn't too shabby. Normaly in games you end up wondering where the "intelligence" part comes into play with the characters who are suposed to aid/help you out in a game. But the girl actually kept up her end as long as you didn't smack it completely out of whack. The graphics were good too, though there was only one screen to look at.
The only thing I thought off was your comment that the reasonable scores started at 5,000. I died out at about 2,900 at my best... granted I wasn't trying to master the game or anything, so I am sure with more practice I could do batter, but how long does it take to reach 50,000?
The little object you hit around in Badminton is also referred to as a "birdie". Which is probably a little more kid friendly than the "shuttle", or "shuttlecock" nomenclature also attributed to said object.