Can a ten year old run in the Olympics?
Olympic track events use the age limits established by the IAAF, which prohibit children under 16 from taking part (certain events, like the 10,000 meter run and the marathon, have even higher age requirements).
There is not an Olympics for ten year olds but at your school you may want to talk to your coach about keeping the times for the mile run and then having a record for the fastest of both boys and girls. I assume you guys are in the States. In Sydney about 5.20 is the top level - there'd be 4 kids running around that right now. And most have only just turned 10.