These streams already exist. One of the major issues I see wit this is it assumes a child at 15 years old is capable of making this choice and understands all the implications. I think back to grades 9 thru 13 (Canadian), thank God it's not so long ago, but I realize decisions I made then were primarily based on emotion, testosterone and some social influence. Could I really have imagined life 15 years later? Absolutely not.