Most of the exhibits have been updated. It's a great place to get some exercise though try to walk early or at times there aren't crowds (like overcast or wintery days). Lots of picnic tables with bathrooms but don't surprised if part of the area is being used by a group. There's usually more than enough tables. There are also covered tables near the lake on the far side of the zoo near the polar bears. There are cafes for food but many people bring in picnics (often pulling wagons with coolers).
Depending on the size of your family it may be worth it to purchase a membership rather than individual tickets. We only need to visit twice to make it cost effective for us. We also get the membership that includes parking.
Our children have always enjoyed the classes and even the parent/child offerings are fun. The special events are ok but it's usually pretty crowded and we prefer to enjoy it on less crowded, non-event days.
We're often in Milwaukee and with a membership we can often stop in for a quick visit--a picnic or just to walk and get some fresh air and not feel we have to stay long to "get our money's worth".
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