Cleveland Metroparks Zoo is adequate. It's here, isnt it? If it weren't here you'd be whining about how there's "nothing to do in Cleveland."
It's one of the cheapest places to hang out -- especially if you're a member. Buying a membership is totally worth it, too. CMZ is the type of place you can decide to visit in the middle of the day and stay for a few hours and not feel guilty about not seeing the gorillas. Come back tomorrow and it's all still here.
It's easy to get in and out. Parking is absolutely free. There are bathrooms everywhere and they're surprisingly clean.
It's never really crazy crowded -- unless you go on free Cuyahoga county resident Mondays in the summer. Sometimes it's annoying and full of kids who bang on the glass (and parents that allow them to) and parents who call every primate a "monkey".
The dinosaurs thing is pretty cool. Kids really seem to enjoy that -- so pay the extra buck to check that out, cheapskate.