Unlike many countries defined by a shared ethnicity, history, or religion, America is largely defined by a set of shared ideals and behaviors.

Most important are individualism and agency. In many cultures, the primary unit of society is the family or the community. In America, it is the individual.

Americans are raised to believe they are the authors of their own lives. We value self-reliance, personal space, and the right to define yourself:

I would tell any income student that you will be expected to make your own choices about your major, your schedule, and your beliefs. Advisors will guide you, but they won't tell you what to do. That's because Americans don't want to be told what to do.

Because we don't share a common bloodline, the Constitution serves as our unifying document:

Americans are famously litigious and obsessed with rights (Free Speech, Due Process). You will likely hear students debating rights and laws passionately. The belief that "no one is above the law" (even if it's not always applied) is central to our beliefs.

America is deeply anti-hierarchical in its social mannerisms:

Some international students may be shocked by the way college students dress for lecture or address their professors. Don't mistake informality for a lack of seriousness. An American can be joking with you one minute and doing ruthless business or academic critique the next.

Time is a resource:

In the U.S., time is viewed as a commodity and being late is often considered disrespecting of the other person's asset. Efficiency is important, people prefer conversations that get straight to the point.

America is a peaches culture vs a coconut culture that you might see in some parts of Europe. Europeans can be hard on the outside, seemingly stoic or distant at first but friends to the end once you break the shell. Americans are friendly and engaging with strangers. However, this friendliness is often a social lubricant, not an offer of deep intimacy. International students often feel confused when an American is incredibly nice one day but doesn't invite them over for dinner the next. Americans keep their private life private.

I would definitely tell any incoming student that really wants to stand out to focus on participation. It's oftentimes graded. In some settings, students are expected to be quiet and listen to the professor. In the US, may classes want the students to debate with one another or offer their opinion. Even if it's not graded or expected, engaging with one's professor outside of class or with other students will make a student stand out.