I spoke a bit about testing at the January faculty meetings, but here’s some more of my thoughts on this topic. It’s okay if you don’t agree with me, but I’d like to make sure you at least have an opportunity to think about these things.
There are valid reasons NOT to test your students. Perhaps they have a documented learning disability which would preclude accurate results from a standardized test. They may have a test phobia, or become over-anxious in a timed environment. Your family may not have the money or the time to devote to a standardized test. But, if there is no particular reason that your student cannot test, then it is a good idea to get your child accustomed to taking tests.
The reality is that test scores are used in many different ways in life. A homeschooling parent can use them as an objective measurement of a child’s educational progress. Never use an achievement test as the ONLY measurement of educational progress. But it is a useful tool as you consider your total educational program for your students. When you receive the results, you are able to evaluate the effectiveness of your teaching or choice of curriculum. It there is a strength, you probably already know. But if there is a weakness, then you can make changes to address that.
If your student has never tested, then you need to make sure the anxiety level is reduced, both in you and in your student. The younger you start, the easier it is to avoid text anxiety. A lot of students do not test well. But you need to know this before your students are in high school and taking college entrance tests. If you wait to begin testing when your students are in high school, and he or she does poorly the first time, a lot of hand wringing follows. Parents begin questioning their student’s abilities, or their choice to homeschool, or whether or not he or she would have done better with another teacher. Once your student is in high school, you don’t have as much time to adjust to testing as you do if your student begins testing in elementary school.

As your students get older and face high school and college, test scores are used as entrance requirements: for college, for scholarships, as pre-requisites for college and high school classes, for honor societies, etc. Your student’s GPA and ACT/ SAT test scores are the two major qualifying items for most college scholarships.
This is simply the reality of the world. As Christians we are to be in the world, but not of the world. As homeschoolers, we do not have to model our schooling after the public or private system. However, we do not know what the Lord has in mind for our children as they move into adulthood. Parents should prepare children with a broad education, equipping them as adequately as possible for whatever God has planned for them.
For employers, colleges, military, etc. who may be considering your student in the future, a test score gives a comparison of how your student ranks next to other students who have taken the same test. It gives them an objective opinion of your student’s achievement. If two students take the same test, then their scores give some idea of how those two students may compare academically, sort of like comparing apples to apples.
A test doesn’t reflect a student’s potential, or his abilities, or provide any insight into his character. Many students become productive citizens without ever taking a test. If you decide not to have your student tested, you won’t be damaging your child. There are valid reasons NOT to test your student. However, in my experience, a average ACT/SAT, or Stanford score, along with a diploma, gives an objective measurement of your student’s achievement and tends to provide enough extra information to affirm what you already know about your student, that they have received a high school education.