On the whole the students I taught at neighborhood schools were willing to take tests, both ones I created and standardized versions. That being said, there were always a large enough number of students who put their heads down, didn't try, complained loudly, or walked out of the room. I found myself begging students to try their hardest. My one major argument: if you leave it blank, you guarantee yourself a zero; if you try, you could get partial credit. Still, it didn't matter that much.
In comparison, when I administered midterms to my current students last week they focused just fine. There were a few times when a head was down for a few minutes, but that student got back to work after a brief respite. No begging necessary.
So why does this happen?
Again, I am no expert at teen psychology but I think the issue is mainly one of preparation and expectation. Students at my current magnet school (for whatever reason) are mostly at the level they should be for high school math and so have the background knowledge to push ahead. Additionally, they have a positive association with putting effort into tests.
In contrast, my students at neighborhood schools were not as well prepared and, I think, felt that if they tried and failed it was a determination on their future. Instead of putting effort in only to be told they had failed, they put no effort in and so could not be blamed for the failure. In my belief, this view was held by many of the students who decided to take a nap instead of finishing their Algebra tests in my previous schools.
I'm not sure exactly how to solve this one but I think one major factor that would help is having fewer unprepared students in one classroom. Peer pressure can be a strong thing and if the one or two less-prepared students see everyone else putting in effort, they might just do the same.