The most common and most likely answer to this crossword clue is the 6 letter word PREPPY
I've seen this crossword clue in The Times
P
R
E
P
P
Y
More clues leading to the result PREPPY
Buddy explains!
The straight part
We know that "US student" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case us student = preppy.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does PREPPY mean?
PREPPY noun- A student of a prep school.
- Relating to things (such as clothing) that are typical of students at prep schools