Every spring, New Jersey students in grades 3 through 8 sit down for the NJSLA, the state's official standardized test. Basically, that's the group of kids who are actually hitting grade-level expectations in math, not just scraping by. We lined up all 465-plus districts in the state by that proficiency percentage and sorted from lowest to highest. The 25 districts sitting at the very bottom of that list made the cut here. So a district with 20 test takers isn't quite an apples-to-apples comparison with a district that tested 2,000 kids.