Ключевые слова: 1, 1012 years, 79 years, academic, alone, aspiration, brass instrument, caucasian, child, children, class, classes, educate, educating, education, educational, effort, enjoy, enjoyable, enjoying, enjoyment, exerting, exertion, females, girls, goals, half length, halflength, high school, high school student, high schools, highschool student, horn player, horn players, human, human being, individual, indoors, inside, instrument, kid, kids, learn, learning, music, musical, musical instrument, musician, one, one person, one person only, people, person, photography, practice, practicing, preadolescence, preadolescent, preteen, preteen girl, school, students, studious, study, studying, trombone, trombone player, trombonist, trombonists, trying, tween, whites, wind instrument, young, youngster,