Despite the fact much of the action takes place after the Christmas break, it is almost always early autumn when the actors are outside. Given this is supposed to be in Maryland, the trees in the winter and early spring should be bare, not heavily covered with green and yellow leaves.
During the I-Day formation, Donnie Wahlberg (Lt Cmdr Burton) has a mustache as he sits on the stand. This was acknowledged by the director and producers in their commentary on the DVD, and they left it in because you can barely see it and they have several creative ways of explaining away its absence later. However, just the day before he was clean-shaven when he met with Jake at the shipyard.
At the boxing tournament, none of the boxers wears headgear. While a lack of headgear makes it much easier to see the actors' faces, headgear is mandatory for any tournament at collegiate level, and especially an intramural one.
There is no time limit for the obstacle course. Twins would not be kicked out for failure to complete the course in the time limit.
Plebes aren't allowed to drink, regardless of age, even when on leave.
Huard was eating 'contraband' as he walked up to weigh in. In real life this would be an integrity violation, resulting in an honor board, and possibly removal from the Academy.
If Cadet Cole had spent three years in the US Marine Corps before being accepted into Annapolis, he would have been wearing a Marine Corps good conduct ribbon.
In the opening boxing scene, the words on the plaques in the background are in mirror image.
Cole says, "someone get a Medic." No sailor would ever say that. They would say "someone get a Corpsman."
One of the focal points in the movie is the destroyer under construction in the shipyard across the river. The ship being built is a Spruance-class destroyer, most of which were actually built in the 1970s and are now being decommissioned as obsolete or being sunk as gunnery or missile targets.
There is no shipyard anywhere near the Naval Academy in Annapolis, MD. The academy is surrounded by very ritzy suburbs.
A boom mic is visible when they're reviewing the troops after Christmas.
Named after the USS Triton, The Triton Light contains water from the 22 seas the USS Triton saw during its employment in the navy, not 7 as mentioned in the movie.
Cole describes himself as a "soldier". A Marine or former Marine would NEVER describe himself or herself as a "soldier", because a "soldier" refers to someone in the Army. A Marine would describe himself or herself as a "Marine".
At the end of the movie Jake kisses Ali while both of them are in uniform. This is a flagrant violation of the UCMJ (uniform Code of Military Justice) and at a minimum would have them both up at a Captain's Mast.
In the scene finals where Supt. Carter addresses plebes before summer leave the Maryland State flag is displayed upside down.