Before making a decision I would need to see some socio-economic data for the school.
In our area (greater Puget Sound) you can get a report that not only ranks the school based on test scores, but based on what their test scores *should* be (based on income levels). You can get a school in a very poor area, with many ESL students and high turnover that performs below the state average BUT it is much better than they statistically "should". You can also have a school that performs above average, but given their neighborhood, they *should* be performing a LOT better. I would have to assume that the first school has some motivated teachers and would actually be more interested in sending my child their (think that the teachers are really working).
Additionally, if you are interested in test scores, page 8 & 9 seem especially relevant given that they have a specific goal, are working towards it and actually exceeding their target each year.
Now, ignoring the test. I find standardized tests like that to be fairly meaningless. They are generally, at this point, not compossed by educators by *test selling companies.* They do not necessarily have any correlation to actual knowledge or academic success. Low test scores *in and of themself* do not bother me at all. Realistically, the emphasis on test scores in a school would disturb me more.
I would tour any school before I allowed my child to go there. Get some answers to things that concern you (PE, recess, music, homework, bullying, etc...). That, to me, is a bigger deal than the result of a test.