Is Testing a Necessary Evil?

As I am entering into homeschooling kindergarten I am evaluating the place testing will have in our home. This is going on at the same time I am hearing about all the testing going on in the public schools. Between No Child Left Behind and the new High School Exit Exam here in California, we are all hearing the horrors of "teaching to test". I hear friends of mine who are teachers complaining all the time that all they do is test. I hear parents complain and some do even more than complain. I know 1 parent who has decided that all the testing is ridiculous so she pulls her kids out for the testing (I do not endorse this method, play the public school game or don't). She says the kids no longer even take the tests seriously so they make patterns on the Scantrons and other nonsense. So what is the purpose for all this testing? It is for money right? I disagree and put forth another theory. Some teachers and schools do a bad job and we need to monitor the progress. We have been getting kids coming out of high school who aren't ready for college, balancing a checkbook or just being an informed adult.
As I started thinking about how much testing my own kids needed, being homeschooled, I started really looking at the reason for testing. I think that testing is really just a way to mark a child's progress. So in theory, testing is not needed. Just be diligent in what the students are learning and watch their progress on their homework. But, it isn't that easy. The National Department of Education says that they get $71.5 billion a year and that is only 8% of the money sunk into public schools. What are we getting in return? Not much. According to the Secretary of Education:

Currently, our 15-year-olds rank 24th out of 29 developed nations in math literacy and problem solving. Almost half of our 17-year-olds don't have the necessary math skills to work as a production associate at a modern auto plant.

The testing provides an element of transparency and the ability to see where the problems are. We, as a nation, have tried to just throw more money at the problem but that has proven to be a mistake. Money without accountability is not helpful and if you are unsure look at Washington DC. They spend more per student and test the worst in the nation.
Yes, I understand that teachers are teaching testing material instead of concepts but at least that is something. According to Secretary Spellings, in his testimony before Congress:

With No Child Left Behind, we've laid a solid foundation of student achievement. Scores are at all-time highs for African-American and Hispanic students, especially in the early grades. Over the last 5 years, more reading progress has been made among 9-year-olds than in the previous 28 combined.

How many times do they have to hear these individual facts before they have an effect? Well, it may be a path worth taking. Compare that with the High School Exit Exam here in California. Over at Why Homeschool there was a good analysis on the test:

There are 60 Mathematics Sample Questions. The first 50 problems are on concepts taught in grades 6 and 7. The last 10 problems require some basic algebra. If students only need to get 50% correct to pass, and they get several chances (over 2 or 3 years) to pass, it doesn't seem unreasonable to require students to get a passing grade to get a diploma.

Is it reasonable to expect them to pass? Well, according to the LA Times, at least 10% of seniors can't pass it. While I think testing isn't the best cornerstone to education, I think that while we are paying we should have some sort of accountability. We as a nation are not dumping millions of dollars into a system to produce people we will have to continue to support forever. If I am not paying for other's education, you can run it however you would like but until then I believe the testing is here to stay.