Pennsylvania requires that students in grades 3, 5, and 8 take a standardized test. While this can be looked at as one of the unnecessary evils, we have the opportunity to see the bright side that it gives us an idea of what our children are retaining, and we can find comfort that even if they don't test WELL it doesn't have to negatively affect us.
When your student takes the exam of your choice, you need to include the results in your end of the year evaluation. Your evaluator will mark off that "Yes" you completed the exam and that is it! The results are not required to be sent to the school district you simply keep them for your records in case any questions ever come up.
I am not affiliated with any of these links! They are just the resources that I have come across in trying to better understand our testing options. But the 2 that I hear most often used are the CAT and the Stanford!
The PA Home Education Testing Requirements | Pennsylvania Home Educators Association (phea.net)