I believe the rule for applying for a 4yr NROTC scholarship (like a HS student) is you can't have completed 30 units by the time of your application.
Correct. Requirements from the NROTC website:
* U.S. Citizenship
* Not less than 17 years old by Sept. 1 of year starting college and no more than 23 on June 30 of that year
* Must not have reached 27th birthday by June 30 of year in which graduation and commissioning are anticipated
* Applicants with prior military service may be eligible for age adjustments for amount of time equal to their prior service, on month-by-month basis, for maximum of 36 months, if they will not reach 30th birthday by June 30 of year graduation and commissioning are anticipated
* High school graduation or equivalency certificate by August 1 of year of entrance into four-year NROTC Scholarship program
* No moral obligations or personal convictions that prevent conscientious bearing of arms and supporting and defending the Constitution of the United States against all enemies, foreign or domestic
* Physically qualified by Navy or Marine Corps standards
* Students w/30 or more semester hours or 45 or more quarter hours of college credit upon application or students already enrolled in NROTC College Program are not eligible for four-year NROTC Scholarships; these students should see professors of naval science at host university's NROTC unit to discuss other scholarship opportunities.
* Students may apply for only one of three program options-Navy, Marine Corps or Nurse
* Active duty Navy applicants are ineligible to apply for NROTC program through COMNAVCRUITCOM. Active members of other branches of the military may apply if granted a conditional release. Individuals who are scheduled for boot camp may apply provided they complete all required application evolutions (i.e. strong interest inventory, officer interview, etc.). NSTC will accept teacher evaluations, transcripts, and ACT/SAT scores dated after the applicants ship date.
* Navy and Nurse-option applicants should apply online or through Navy recruiting offices
* Marine Corps applicants should apply online or through Marine Corps recruiting offices
* You may start the process of applying during the second semester of your junior year of high school. Before the application can be finalized and forward for selection consideration, you must ensure that a copy of your complete transcript including your entire junior year is forwarded to your recruiter.