How important are school zones in Buy and Hold?

[Malcolm Lawson]

I am currently looking at homes for my second investment property.  I noticed that one county near me has all 7, 8, or 9 school ratings and another county near me has all 4, 5 or 6 school ratings.   And of course the houses with better schools cost more then the ones with the poor schools.

My question is should I be focused on the school zones or should I just be focused on how much cash flow a property can produce?  Have any of you ever noticed a correlation between school zones and "quality" of tenants?