My preschooler loves the Columbus Zoo's combination of standard animal watching, (especially the manatees), rides, and stellar playgrounds. There is a food court but it tends to be quite expensive. Parking and admission fees can add up. But their memberships are extremely reasonably priced and include free parking -- with membership and a bag lunch, this is an inexpensive and exciting day out.
For more info, see www.colszoo.org
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