Have you considered the fact that maybe the Title One reading kids just "don't care" because they are frustrated. Have you tried creating alternative tests or study guides for the students that have a difficult time reading? Do you read the test to them? This might improve their overall performance. Once they realize you are willing to bend over backwards to help them they might be willing to try harder to work for you.
I always have to remind myself that I am testing content area material and not reading skills.