The student center is at the heart of campus, right next to Mac Field, and its address is:

To get to Grinnell from...

I-80: Take exit 182 north three miles on Highway 146. Turn east (right) on Sixth Avenue (Highway 6). Proceed two and one half blocks on Sixth Avenue to the Grinnell College campus.
The Twin Cities: Take I-35 south to Des Moines, Iowa and then take I-80 East. Take Exit 182 off of I-80, and drive north three miles on Highway 146 until you reach Grinnell. Turn east (right) on Sixth Avenue (Highway 6). Proceed two and one half blocks on Sixth Avenue to the Grinnell College campus.
St. Louis: Take I-70 west to Columbia, Missouri and then take Highway 63 north to New Sharon, Iowa. At the stop sign in the center of New Sharon, Iowa, proceed straight to take Highway 146 north to Grinnell. When Highway 146 passes under I-80, drive for three more miles until you come into Grinell. Turn east (right) on Sixth Avenue (Highway 6). Proceed two and one half blocks on Sixth Avenue to the Grinnell College campus.

Grinnell is about halfway between Des Moines and Iowa City right off of Exit 182 on I-80.

Driving Times to Grinnell:

Chicago to Grinnell: 5 hours
Twin Cities to Grinnell: 4.5 hours
St. Louis to Grinnell: 5.5 hours

Still lost? Check Google Maps.