Youth vs Youths

‘Many youths here have their sight set on non-prescription glasses — all in the name of fashion ... [Valerie] Teo is one of the many youths wearing glasses as a fashion statement ....’ (Sunday Times Lifestyle, 7 September 2008).

The word youth is one that the Straits Times never seems to get right. (It was also a problem for the Ministry of Education master teachers when they started the Sunday Times English as it is Broken column two years ago.)

In Standard English, the word youth has four different senses. The two that concern us here are (Oxford Advanced Learner’s Dictionary):

a. [C] (often disapproving) a young man: The fight was started by a gang of youths.

b. (also the youth) [pl.] young people considered as a group: the nation’s youth, the youth of today, youth culture, youth unemployment.

The word youths, as used in the ST article, is plural, which means it is intended to be countable (e.g. a youth, many youths), and includes females (Valerie Teo). This is Singapore English usage.
Contrast this with Standard English, where the countable use of the term has negative overtones and refers only to males (Sense (a) above).

The article clearly does not intend to refer to ‘young people considered as a group’ either, so Sense (b) is out too.

The most appropriate phrase is, simply, young people:

Many young people here have their sight set on non-prescription glasses — all in the name of fashion ... [Valerie] Teo is one of the many young people wearing glasses as a fashion statement.

I’d also change sight to the more idiomatic sights. (If sight was intended as a pun, it was a rather lame one.)