This weekend at the Second Life Community Convention in Boston, Linden Lab CEO Philip Rosedale gave a keynote address during which he announced the direction he was taking Second Life to keep it sustainable and growing. Among the big changes he reported are that Linden Lab will be very soon closing the "Teen Grid," the youth version of Second Life restricted to 13-17 year olds and a small number of approved adults.
Initially they will be bringing over the 16 and 17 year olds on the Teen Grid over to the "non-mature" sections of the Main / Adult Grid of Second Life. Later on, they will be figuring out a way for younger users to get to Second Life, in some limited capacity.
You can watch Philip Rosedale's complete keynote above or at this link. Skip ahead to the 0:38:00 mark to see his remarks specifically about the Teen Grid. And at the 1:04:00 mark there is a moving comment from teacher Peggy Sheehy: "It's a tragic error for you to close the Teen Grid for the younger students."