HONOLULU (AP) — Scores by recent high school graduates in Hawaii slipped slightly in all three subjects tested by the College Board SATs — reading, writing and math. The 8,195 members of the class of 2008 who took the college entrance exam scored an average of 502 points out of a possible 800 in math, down from 507 last year. The students averaged 481 in critical reading, compared with 484 last year, and 470 in writing, down from 473 in 2007. Nationwide, scores remained unchanged from last year, averaging 515 in math, 502 in reading and 494 in writing. The state Department of Education said Tuesday that overall scores for students in island public schools and in religiously affiliated schools declined slightly in all three subject areas. But scores for independent school students improved in math and writing, while going unchanged in reading, the department said.