Hey aczerniak, I live in Chicago as well. I've done observation hours in multiple settings: hospitals (acute, inpatient/outpatient/pediatrics at Resurrection, Children's Memorial), clinics (Athletico, ATI), SNF, and the schools (Northside Learning Center).
You can easily call an Athletico clinic in your neighborhood that offers occupational therapy. I used to work as a rehab aide at Athletico. They usually allow pre-OT/PT students to observe right away. They understand what it's like to be a student and how important hours are.
There are a ton of pediatric clinics you can observe at as well. I did a few hours at Northshore Pediatric and in any special ed school in the Chicagoland, suburban area. I currently lead play therapy groups and work with children with autism under a behavior analyst and OT.