Cross Cultures Accepted

Generally speaking, I like to moan about the English and American cultures crossing over- it comes from my need of perfection of English grammar and spelling with a year spent in Finland listening to everyone's American English presentations, regardless of where in the world they were from. But just once in a while when I realise I was wrong I will back down and apologise- and this is one of those moments- so make the most of it! In a post about school back in February, I was aghast when one of the kids I was working with told me he'd been playing baseball the night before. As I said at the time- who plays baseball in the UK?!? Rounders, yes, but baseball?? Last night my little brother showed me (well, more accurately, my mum decided it was time I learn) how to play on his wii. So I was competing against Simon at tennis, golf, bowling and...baseball. It suddenly dawned on me that this is where the kids get it from- and more than likely they weren't playing real baseball (like we did rounders- back in the day ;-)) but were playing on the wii, which in itself is American English. Never one to pass up an opportunity to make some comment though- what on earth does 'spare' mean in bowling?? We have strike if you knock them all down in one go, and if it takes you two go's then its a 'half-strike'- that makes sense. Where does 'spare' come from for a half-strike and just generally why??