I don't think it's a conceptually hard problem.
As I said in my response to Viliam_Bur, it's easy to say "find out what the relevant factors are, address those," much harder to detail exactly how one works out what the significant factors are, let alone how to best address them.
Keep in mind that sorting by IQ is still a strong political taboo, and more politically viable proxies, such as SAT scores, are liable to be corrupted by factors such as SAT prep. Plus, target minorities are subject to an IQ gap which may be due to some of the cultural and/or economic factors which the policy is intended to address in the first place, in which case sorting by IQ would compound the original problem.
Keep in mind that sorting by IQ is still a strong political taboo,
With who? Not most Americans, I'd bet. Most Americans accept as obvious that IQ correlates with potential for higher learning.
the cultural and/or economic factors which the policy is intended to address in the first place
So the policy is intended to remake society, not find the students with most potential, or give some extra help to disadvantaged students? This is just a tool to make society look like you want it to look?
Be clear what the goal is.
Related: Heuristics for Evaluating the Soundness of the Academic Mainstream, Admitting to Bias, The Ideological Turing Test