Union Club Hotel
-The closest parking lot to the Union Club Hotel is on Grant Street between State and Northwestern. It is free for hotel guests.
Math Department
-The closest parking lot to the math department is on the corner of 2nd and North University Street. It is free on weekends and after 5pm on weekdays. To park there during the week, you need to purchase and print a day pass here: http://www.purdue.edu/pat/mainnav/parking/permits_visitors.html. It is $5 per day.
Note that the Math Department and the Union Club are within walking distance of each other.