Rachel,
My view (personal opinion alert!) of testing is that it is a legal requirement that we do and think, “we’ve kept the law” and move on.
However it’s other use is that it gives us a picture of where the child is in their learning. It is a good way to see where their strengths and weaknesses are. That way we can give big pushes in the area of their gifts and little nudges in the area of their weaknesses. Or we can make a plan. Or we can say, “well, I already knew they would be getting that in ___ grade so it really doesn’t matter” and do nothing.
As far as what they know now (and I’m guessing that your children are a little young), it may very well show up that they are not where the ps kids are in a couple of areas but that’s because they are learning in a different way. They are also not being taught with the test in mind, as a ps teacher would. They will get it, just not yet. The flipside is that your children will know lots of things that aren’t even on the test.
Blessings,
Cindy