The MARADMIN 346/19 states this as far as qualifications:
3. Basic eligibility requirements for NROTC Scholarship Applicants:
A. Be a U. S. Citizen.
B. Be 17 years of age by 1 September of the first year of college and younger than 27 on 31 December of the year in which college graduation and commissioning are anticipated.
C. Be a high school graduate or possess an equivalent certificate.
D. Be physically qualified as set forth in Ref (A) and be within height-weight standards in accordance with Ref (B).
E. Personally exemplify and display the following:
(1) Character - Morally qualified and possessing officer-like qualities and character.
(2) No record of military or civil offenses. Marines awaiting trial or sentence, on probation, under suspended sentence, or under any other type of military or civil restraint as a result of violation of law or regulation or who have been convicted of a misdemeanor, the nature of which manifestly renders them unfit for commissioned service, are not acceptable.
F. A score of 74 on the Armed Forces Qualification Test, a composite score of 22 on the American College Test (ACT), or a combined score of 1000 in Math and Evidence Based Reading on the Scholastic Aptitude Test (SAT). SAT scores must be from the same test. ACT and SAT scores must be from the most recent test. Applicants must authorize release of SAT and ACT test scores to the NROTC Scholarship Program by indicating the four-digit program code, 0656, on the test registration form. Applicants should also be prepared to hand deliver test score verification to their local Recruiting Station Executive Officer (RS XO). No waivers for test scores are authorized.
G. Meet admission requirements of an NROTC affiliated college or university of choice.
H. Cannot have more than 30 semester hours or 45 quarter hours of college credits at the time the application is submitted.
I. Time in Service: Active Duty or Reserve Marines must have at least one (1) year Time in Service as of 1 October 2019. This requirement is not waivable.