Are there any good private elementary schools in Wappinger?

The only one I can think of is the Randolph School on Route 9D near Hughsonville. It's small, private, exclusive (as far as I know) and runs from elementary school straight up into high school. I hear it's very good.

Some websites will also list St. Mary's as being in Wappinger, but its on the Poughkeepsie side of Wappingers Falls (the village is split between two towns -- still, it's the nearest-by Catholic school option for Wappinger folks).

Yeah, there is actually a great institution called The Randolph School which actually serves students from the ages of 3 to 10. There is also St. Mary's Catholic School which runs from Pre-K through 8th grade.