The NAEP provides ethnic averages and percentiles in both reading and math for 8th graders in 2019. I chose 8th graders because they are the oldest age group for which they have nationally representative samples, since 12th graders only include those who have not yet dropped out of school. Note: scores are reported on 0 to 500 scale.

Reading

	whites	blacks	Hispanics	American Indian/Alaska native	Asian/Pacific Islander	Multiracial
90th percentil	314	288	297	293	326	312
Average	272	244	252	248	281	267
10th percentile	227	197	202	198	232	218
Estimated SD	34	36	38	38	37	37

Math

	whites	blacks	Hispanics	American Indian/Alaska native	Asian/Pacific Islander	Multiracial
90th percentil	339	306	314	308	364	337
Average	292	260	268	262	310	286
10th percentile	245	215	222	215	252	235
Estimated SD	37	36	36	37	44	40

Although the NAEP is not an IQ test, the correlation between IQ tests and scholastic achievement tests is about as high as the correlation between two IQ tests, making them statistically equivalent in the general population. Further, the main reason people care about racial IQ gaps is because they translate into racial learning gaps, so converting to IQ seems appropriate and the advantage of using the NAEP to infer group IQ gaps is the excellent sampling this data has among subjects who have spent their whole lives learning these skills.

	reading IQ	math IQ	composite IQ
whites	100	100	100
blacks	88	88	86
Hispanics	91	90	90
American Indian/Alaska native	89	88	88
Asian/Pacific Islander	104	107	106
Multiracial	98	98	97

For technical details on how these scores were converted to IQ, see technical note below.

Technical note

The reading, math, and composite NAEP scores were converted to IQ by equating the white NAEP means with 100 and the white NAEP SDs with 15. The reading and math SDs were estimated by subtracting the 90th percentile NAEP scores from the 10th percentile scores and dividing by 2.53 (the bell curve Z score difference between these percentiles) .To determine the white mean of the composite score, we simply add the reading and math means, which gives 564. The white SD of the composite score was crudely estimated by assuming the reading and math correlation among all white 8th graders taking the NAEP is the same as the correlation among all college bound 17-year-olds taking the SAT (r = 0.67 according to Herrnstein and Murray). Using the formula for calculating the composite SD (from page 779 of the book The Bell Curve by Herrnstein and Murray):

This gives a composite white SD of 65.