This looks like a mix of some real suicides with a fake urban myth. It's similar to the burundanga stories or the LSD tattoos stories, but in this case they mix some sad cases to make it more credible.

These stories used to circulate as email chains, until some school or police department take it seriously and make some official warnings.

http://www.snopes.com/blue-whale-game-suicides-russia/

http://www.snopes.com/crime/warnings/burundanga.asp

http://www.snopes.com/horrors/drugs/bluestar.asp