My students took a practice reading test (a la the state test) over the last two days. I try to minimize the importance of these things in their eyes so they don’t feel too much pressure. This involves confronting a lot of the stereotypes they have about testing.
As we headed into the room after lunch, I asked the students to get their desks into rows. One boy who has shown a lot of personal and academic growth this year said something along the lines of, “Oh man, the test is so important.”
Of course, the content is way past the level of most of my students, and it frustrates them (try though they might!), so I try to downplay that kind of talk. I said, “Listen, we know you’ve done very well in school this year. That’s important, too.”
He agreed.
From the Desk of Mr. Foteah 
So true, students have to see these tests as one piece of their overall academic profile. It’s important that they understand that these tests, when used well, help educators to better meet their needs and help them progress. I experienced a similar event recently. You describe the scenario well.
In Ontario, our EQAO tests in Grade 3 and 6 get some kids very stressed out (and their parents too!) and unfortunately, the test results really amount to nothing. They don’t receive the results until well into the next school year, the results don’t have anything to do with Special Education placement; basically the results are used to rank schools and boards and allow some administrators to brag about how great their school is compared to others.
One of the most frustrating things is that when the results get published, they often neglect to account for Special Education, or ESL students.