Here’s a pet peeve that probably only bothers me: I get disturbed when a private school partially assesses the quality of its academic program by comparing the SAT scores of its graduates to either national or state averages. The children who attend private schools are those who’d be expected to do well on the SAT in the first place: they come from families able to afford a private education, and (sadly) SAT scores are highly correlated with family income. The table below shows the average SAT scores in 2009-10 based on family income and is taken from the above link.
| Family income | Critical Reading | Math | Writing |
|---|---|---|---|
| All students | 501 | 516 | 492 | Less than $20,000 | 437 | 460 | 432 |
| $20,000, but less than $40,000 | 465 | 479 | 455 |
| $40,000, but less than $60,000 | 490 | 500 | 478 |
| $60,000, but less than $80,000 | 504 | 514 | 492 |
| $80,000, but less than $100,000 | 518 | 529 | 505 |
| $100,000, but less than $120,000 | 528 | 541 | 518 |
| $120,000, but less than $140,000 | 533 | 546 | 523 |
| $140,000, but less than $160,000 | 540 | 554 | 531 |
| $160,000, but less than $200,000 | 547 | 561 | 540 |
| More than $200,000 | 568 | 586 | 567 |
Note that students who comes from families earning between $60,000-80,000 are at about the average for the country.
Based on this chart, my personal opinion is that private schools of average academic quality should produce graduates that score, on each of the three sections, about 35 or 40 points higher than the rest of the country. However, for very exclusive and expensive private schools, the difference should be 50 or even 60 points on each section.
NB: These comments are strictly limited to this one assessment of the academic programs of private schools. There are other assessments of academic quality besides the SAT, and there are plenty of nonacademic reasons for parents to choose a private education if they have the means to do so.
Mean Green Math 