We are planning on spending the weekend in Chicago for my husband's 40th birthday. We reserved a trolley to transport up to 30 of our friends on Saturday night for a pub crawl. His birthday just happens to fall on St. Patrick's Day, which should be a blast. Anyway, we would like to have something fun to do during the day (Saturday). Museums are great, but not for this occasion. We live a few hours away, so we don't know all there is to do in Chicago. There may be 12-25 people joining us. I've done whirly ball before, which was fun. I appreciate any ideas you have for people (mostly) in our 40's, but a fun group.Thanks!