We just finished a year at St. Ann in Arlington.
We love the curriculum. The community (parent community) is small, fun, not snobby, and they really love & support their kids.
The teachers are great (most are much more qualified than the requirements ask) and they love, love, love the kids.
Since they organize the students into houses they have a small class as a home, but also have friends in upper and lower grades who provide support and encouragement.
One thing I am so impressed with is that they emphasize the laboratory sciences at an early age.
I also really, really appreciate how communicative my son's teachers have been via email.
My other child goes to the local public school. It is 3 p.m. Friday. A note I sent at 7 p.m. Monday has not been answered.
The St. Ann teacher would respond to a "my child was up late and may be dragging today" with 3 updates throughout the afternoon on how things are going.
I don't know the St. Agnes program, but I feel like St. Ann is both a bargain and priceless at the same time.