During the January 15—19 stretch I took advantage of the free days to go to the Shedd Aquarium right on Museum Campus. The next round of free days won’t be until February 5th through the 9th. I recommend acquiring the tickets online so that there is no hassle, confusion, or wait upon entering any of the museums. When I went to the Shedd they can simply scan the barcode of the ticket on my phone. It has been years since I visited the Adler Planetarium or Field Museum so I will make it a priority to swing by when February comes.