LinkedIn (NYSE:LNKD) announced yesterday that it is going to open its services up to minors as young as 13 starting on September 12th. Different countries will have different age limits for when kids can start using the site, in the U.S. kids will need to be 14 compared to China where they will have to wait till their 18th birthday. LinkedIn also plans on opening college pages in which the colleges themselves will run in hope of helping high school seniors decide on which school they will attend the following fall.