After a few first-year introductory classes with 100-200 students, class size rapidly decreases to 5-40 students in upper-level offerings. Labs and fieldtrips are always divided into small groups of students (15 or fewer).
Courses taught by experts in their field
Full professors teach courses at all levels, from introductory to advanced. While graduate students may assist professors in preparation for laboratory work or fieldtrips, all classes are taught by professors.
Students may join a department laboratory and engage in research under the direction of a faculty member and alongside graduate students.