An OAR study plan for the three subtests

NAMI publishes no time or item split by subtest, so plan by your own misses rather than by a weight chart.

1. Diagnose. Take the practice test once, in order, and count misses by subtest.
2. Math Skills. It spans the most topics, so it usually needs the most hours. Rebuild hand arithmetic first (fractions, percents, exponents, roots), then word problems and basic geometry. The topic itself is taught on Arithmetic Reasoning and Math Knowledge; the test's format is on Math Skills.
3. Mechanical Comprehension. Learn the rule behind each machine and practice spotting "no difference" answers: Mechanical Comprehension.
4. Reading. A short timed set most days, checking each answer against the passage line that supports it: the RCT section.
5. Rehearse the conditions. In the final week, take mixed sets straight through without skipping or a calculator.

Popular prep books cover the same school math and physics, so the check is whether they describe the current test. Look for adaptive subtests, a three-choice mechanical section and a 20–80 score. Pair any book with NAMI's own sample questions, which show the item style from the test owner.

Mind the attempt limit as well: at most 3 attempts across the OAR and the ASTB-E together, at least 30 full calendar days apart; the latest attempt counts. Book the first sitting only once your practice misses have leveled off.