Sorry for your DS. Our DS made it to April last year and had the same fate. Great posts above, especially from usmaismygoal. We found this thread, which is a sticky in the USNA section, to be very helpful guidance for college re-applicants.
https://www.serviceacademyforums.com/index.php?threads/reapplying-to-usna-after-a-turndown.61711/
Service academies look favorably upon re-applicants. An improvement in every aspect of the application should be the goal. Different from HS applicants, most service academies will not review a college re-applicant's file until they receive the first semester transcript. I say this to avoid any unnecessary stress trying to get the application completed even sooner than this year's app.
-College grades: college grades will be one of the most, if not
the most important aspects of your DSs application. Going to office hours and getting EI (extra instruction) with professors should be the plan.
-SOEs (letters of recommendation): in the directions for USMA it says "If you are a prior candidate and submitted your four high school SOEs, you may contact us to have them added to your current file." But as the previous poster said, SOEs from two (or three) college professors should be sought after. The guidance my DS got was to ask professors at the end of October/early November with a target of having everything (except your transcripts) completed in your re-application by Dec 1st.
-What was mentioned above about getting the CFA completed earlier is very helpful advice. Try to get this done before college starts if you can.
-For USMA, there will be a supplemental document on ECAs/clubs that will be submitted. This is where your DS can show how they got involved in various clubs and activities in college. Being a participant in a club is good. But leading an organized effort or fundraiser is better. Also, he can talk about what he did over the summer following HS before college started. Even with a college load of 14-18 hrs, most college kids have more time on their hands than they realize.
-SAT/ACT: Agree with the above poster that SATs are supposed to show how well you will do in college. But it's something that can show an improvement in your overall application score. Our DS's verbal score needed some improvement. Over the summer he took a course called Ace Reader, which helped improve his reading speed and strengthened his comprehension. He also took a course in SAT grammar to review/re-learn all parts of grammar. These two courses not only helped improve his SAT verbal score, but they also set him up to do well in university classes. Khan academy is a free resource that can also help.
-Essays: Your DS can use this experience and what he did to improve himself over the next year as part of the narrative of why he wants to attend USMA.
-Thank everyone who helped with the application process and let them know that he will be re-applying.
Getting a TWE is very disappointing. But don't let it define your DS. Service academies admissions boards appreciate perseverance. Good luck to your DS. Feel free to PM me with any questions.