I don't know anything about this particular Lowell High School, but selective admissions at the high school level achieve excellency by filtering out "bad" students, which are usually students from disadvantaged backgrounds.
If a public school is of very high quality, selecting 10 year olds at random is not much less fair than choosing them based on their grades or extracurricular activities or an essay. Unless we assume that high grades, extracurricular activities or essay tutoring are not correlated with family wealth.
If certain demographics are heavily underrepresented (and I don't know if it's the case here), either we must assume that they are less smart (and so produce less "high school material") or we must acknowledge that there is some form of discrimination. The latter being almost certainly true, lotteries and quotas don't look like the dumbest ideas.
If certain demographics are heavily underrepresented (and I don't know if it's the case here), either we must assume that they are less smart (and so produce less "high school material") or we must acknowledge that there is some form of discrimination. The latter being almost certainly true, lotteries and quotas don't look like the dumbest ideas.