When kids “just don’t test well,” that means the testing format or the testing environment is not conducive to the specific child’s needs and the teacher needs to make accommodations. If you believe that the length of the tests or the abundance of concepts on the tests is an issue, you can ask for a 504 plan to be written with an accommodation of shortened tests. This might mean fewer test questions. It could also mean that a longer test gets broken up over multiple sittings (i.e., part before recess, part after recess, or spread over a few days). Another solution would be for the teacher to assess more frequently so that the assessments can be shorter. Teachers can also find other ways to assess than the typical paper/pencil test. These are all solutions that I use with my students.