How do undergraduate class sizes compare at UIUC and Williams College?

Williams offers a much more consistently small, discussion-centered undergraduate classroom experience than UIUC. At Williams, most courses are built around seminars, close faculty interaction, and substantial student participation, especially after introductory work. UIUC has many small classes as well, but its scale means that large lectures are a routine part of the experience in popular majors and general-education courses.

Williams is a residential liberal arts college with a relatively small undergraduate population, so professors commonly teach their own classes and students can expect to be known by faculty. Its signature tutorial format, in which two students work closely with a professor and regularly critique one another’s written work, is an unusually intensive example of its emphasis on discussion and individual feedback. Introductory courses can still be larger, particularly in economics and some sciences, but they are typically not the defining format of a Williams education.

UIUC is a large research university, and class size depends heavily on major, course level, and demand. Introductory courses in fields such as computer science, engineering, business, psychology, economics, and biology may use large lecture halls, often paired with smaller discussion sections, labs, office hours, or recitations. As students progress into advanced courses, many classes become smaller and more specialized, though highly enrolled programs can remain sizable.

For a student seeking frequent seminar-style discussion across subjects and close contact with professors, Williams provides that structure more reliably. UIUC can offer excellent small-course experiences, particularly in upper-level classes, honors sections, research groups, and labs, but students should expect to navigate a larger university environment and take more initiative to build faculty relationships.