For a high school junior competing for admission to a service academy and other highly selective colleges, with regard to rigor, the course load probably is not especially heavy compared to other Candidates but this is measured against what is available at the high school. Most juniors competitive for these schools are taking AP Language or AP Lit if offered. The expected Science sequence is Biology, Chemistry, Physics and AP Chemistry. If HS Biology was taken in 8th grade and HS Chem in 9th and HS Physics in 10th and AP Chem in 11th, then, if AP Physics is offered it is expected Senior year. Math, English, Chemistry and Physics are the most important classes to the service academies. Environmental Science, Civil Engineering and Architecture may be seen as fluff courses regardless of how difficult they may be at a particular school.
USCGA Course recommendations:
http://www.cga.edu/display.aspx?id=14745
http://www.cgaalumni.org/s/1043/images/editor_documents/Parents%20Association/pdfs/class_profile_2015_-_final.pdf
The main issue appears to be the Psat scores. A 59 Math for someone who has already taken Algebra 2 and Pre-Calculus and if it portends the Sat scores is not going to be particularly competitive for a Candidate not being recruited for athletics or other academy goals. The Psat Math tests Algebra 1 and Geometry. The Sat tests Algebra 1, Geometry and Algebra 2. The Act tests Algebra 1, Geometry, Algebra 2 and Trigonometry. If a 58 Cr is indicative of a 580 Sat Cr, that is just barely above minimum levels to be appointed but the Cr score is not counted as heavily as the Math at Uscga. Get an Sat prep book and start prepping. The Sat should be taken the first time the spring of the year taking Algebra 2. Join NHS, membership is considered leadership. It is usually expected that a Candidate shows leadership in at least one non athletic extracurricular activity; however, with working 12-16 hrs a week during the school year, work will be considered an extracurricular activity and leadership in work will be considered.
The Air Force Academy website offers outstanding advice to students prepping for a service academy, rotc scholarship or any highly selective university. Open all links to the left of the dialog box. Be sure to open the "Leadership Preparation" link and read it carefully."
http://www.academyadmissions.com/#Page/Preparation
Page 19 of Chapter 2 of the Naval Academy Catalog indicates classes for a high school student to take to make himself competitive for admission. The classes are arranged in a hierarchy:
http://www.usna.edu/Catalog/
Helpful to read the advice on prepping for college offered on Harvard's website:
http://www.admissions.college.harvard.edu/apply/preparing/index.html
The selection process is nearly identical at the Naval Academy, West Point, and the Air Force Academy, so, whatever is stated on one service academy website or in its catalog with regard to admissions, course selection etc generally holds for the others. The primary difference at UScga is that a nomination is not required so the Loa process is not utilized but instead an early admissions plan is available. Read the following answer and open the links and it should help to explain the selection process and the path to an appointment:
https://answersrip.com/question/index?qid=20101109140847AAZvjcJ
The application cycle for the service academies begins December 1 of junior year when the Air Force Academy begins accepting pre candidate questionnaires from juniors applying to attend the Air Force Academy Summer Seminar. West Point SLS begins accepting pre candidate questionnaires in mid December. The Naval Academy Summer Seminar begins accepting preliminary applications on February 1.
http://www.youtube.com/watch?v=Ao1hC8StUWw
Uscga AIM also begins accepting applications in February. It is best to apply to all since they are similar and going to one indicates to the Admissions Boards at all that a Candidate is well aware of the regimented lifestyle of an academy Cadet/Midshipman. An applicant needs Psat, Sat or Act scores to be considered for the Summer Seminars. An extracurricular reading program looking up unknown words in a dictionary helps with the Cr and Writing sections of the Sat:
http://reading.berkeley.edu/
Colonel Batchelder indicates the attributes SLS seeks in applicants:
http://www.youtube.com/watch?v=XRWc9GiSMCA
http://www.youtube.com/watch?v=ziuUr_golNc
All the summer programs seek pre-candidates with essentially the same attributes. Usna's is the largest accepting 2250, Usafa Summer Seminar accepts 1125 and West Point SLS 1,000. AIM less than 500.
Good Luck!