The great interest stems from its long tradition of competitions between schools. Another factor is that there isn't a club system like the one we have in Europe. In the U.S. most athletes are affiliated with the school which they are attending.
American football, baseball and basketball have the greatest interest, but also other sports can attract large crowds when there are big games and tournaments. In the largest sport, American football, there are schools that attract more than 80,000 to 100,000 spectators for a single game. These sports events are great "happenings" which create something everyone wants to be a part of.
NCAA is a big part of the U.S. college and university athletic life. This organization's main purpose is to coordinate contests and competitions between universities and colleges. Studying is still of great importance since most students will not become professional athletes and they are not going to make money on their sport. An education is something the athletes can fall back on.
The NCAA has many rules that coaches and students must follow during and after the recruitment process. The rules must be followed by you as a student and you want to follow these rules. If you don't you might not be considered in the application process or worse your scholarship can be taken away from you.
Schools are divided into 3 different divisions, I, II and III. Which team a school belongs to depends on the sports facilities and the number of teams in the school. All teams at the school belong to the same division. Teams cannot move up or down because of its sporting achievements.
NCAA Eligibility Center (formerly Clearinghouse) is an organization that assesses the student's competence to practice sports at a Division I or II school. The evaluation by the NCAA Eligibility Center shall is mostly based on the students' academic level. It is compulsory to register with this organization to take part in sport at a Division I or II school.
NAIA is also an association of American schools that organizes college athletics. Members of NAIA are often smaller schools, but this does not mean that the chance for scholarships is smalerl. In many cases it may be easier to get a scholarship from a NAIA school. One advantage of NAIA-schools is that they have a more personal touch and class sizes are usually smaller.
NJCAA organizes sport for all 2-year schools. A Junior College can be a good alternative for those who have a bad result from high school at home. After two years you may choose to apply to an NCAA or NAIA-school.