<p>@voiceofreason66 mentioned data about students +2 SD above average. Two standard deviations is approximately top 5%. The data quoted earlier about the relatively large percentage (17%) of high achievers (those who scored in top 10%) on SAT/ACT whose families are in the bottom 25% of family income should be reasonable to quote as an approximation. Top 10% of SAT/ACT scorers represents approximately top 5% of the 18 year olds (many low achieving students do not take the ACT or SAT or drop out of HS before they would take it). This data on the top 10% (of test takers) represents approximately +2 SD above average for 18 year olds overall. The data showed clearly that these high achieving students are at a disadvantage and a large subset are not matched to appropriate colleges, and the graduation rate of this subset suffers significantly vs. those more fortunate (mostly poor from larger urban areas near elite colleges) students who can get matched to appropriate colleges.</p>