Its a very sad statistic Roger, but also indicates, that suicide, depression and all mental health issues have no respect of age. Those you consider "immature" deserve our support, empathy and compassion, not berating due to their supposed lack of years.
The questions we should be asking, as a civilised society, is why people of such young ages, would be contemplating ending their lives. This is no recent change of focus as I can attest as I am neither young or immature [allegedly] it is a issue that should not be taboo and needs addressing.
How should we behave or approach those who show immediate intent? Ignore them? Tell them to seek help from a medical profession that does not know its arse from its elbow most of the time? I agree that terminology can be a problem, for those outside of the suicidal spectrum, but that does not excuse us or give us reason to ignore those who are in pain or suffering. This is a pro choice forum and I for one, support those who make informed choices about their own existence regardless of age, gender, creed, colour, religion etc etc.