Acreage in Zionsville differs in price depending on the area you are looking to purchase in. For example, you can purchase some land in the Willows for over $150,000/acre, other areas, $75,000/acre. If you really want to be exclusive, you can purchase an acre of land in Willow Ridge for over $500,000/acre!!! That is just for the land!
Zionsville does indeed have some of the best school systems in the state. Hardly any crime. I have lived in Zionsville for 8 years and just love it here.

Newsweek Magazine had an article on the top 1300 public schools in the US. Zionsville was ranked around mid 400's and Carmel was ranked low 900's.

Not sure about the acreage question. I attended Zionsville Schools my whole life and I'm a witness to saying they are excellent schools. I believe where it stands as overall ratings in Indiana, number one and two are Park Tudor and Brebeuf (private schools) then the top public school is Carmel, then Zionsville. Now that's just the high school rating, but the Zionsville School system has 4 stars. The schools are excellent, and the tax rate here proves it.