How to prepare for success?

The Lands at Hillside Farms is a non-profit farm-based educational organization located on a historic dairy farm.  Historically, the public has been allowed free access into our barns during daylight hours.  Three years ago, this might have meant one family coming into the barns a day.  However, this year we  have hundreds and hundreds of people in our barns a day - every day.  This is not a farming community and our "public" does not have basic farm safety in mind - they open chicken coop doors and let all of the birds out, the feed horses despite our signage, they chase ducks, break plants in the greenhouse, etc.... 
I am trying to come up with ways to deal with this wonderful onslaught of community members.  A historic precedent has been set by letting people have free and unfettered access to the barns, but how do we keep everyone and everything safe?

Any ideas?
Thanks
Christine Doherty Pressman
www.thelandsathillsidefarms.org