That can be a big help once students are enrolled in college, Texas A&M's Tacey notes.
"[Some] students do very well on placement tests, but then get here and absolutely struggle because the classroom pace is so fast, and the requirement in our universities that students interact often in class becomes a real challenge," she says.
[Find out more about what has surprised some international students.]
4. Social acculturation: The college experience in the United States doesn't end when class is dismissed, and coming to high school here can prepare students to succeed socially, too.
"[Parents] are probably giving their students a big leg up when it comes to being socially integrated," says John Burdick, dean of admissions and financial aid at the University of Rochester.
The transition to college can be tough for any student, but with a prior understanding of cultural norms, terms, and habits, your student may be better suited to fit into the fabric of a new school.
Texas A&M's Tacey, who works with international students from around the world, says she saw a noticeable difference in the transition period for a female student who had already been in the United States for high school.
"From day 1, she just seemed to have everything a whole lot easier because she already understood the culture and the openness and the way people were," Tacey says.
But for all the benefits a U.S. high school education can provide, the transition might be too much for some students who come here on their own.
"The extra distance and the time changes make it harder for us to communicate with parents; often the kids are dealing with things ... more on their own," says Cassel of Walnut Hill School for the Arts, where international students make up 30 percent of the student body.
"[Parents] have to assess the maturity of their student[s] and their ability to be away from home and handle things on their own, in the moment."
For more international student tips and news, explore the Studying in the United States center.