NCLB forced all states/local education agencies to define learning goals and expected outcomes, then set criteria for achievement levels.  It required them to measure subgoup performance and document whether poverty-related funding was actually leading to reductions in poverty-related achievement gaps.  It prevented LEAs from expecting continued funding for achieving little or nothing with students on the basis that achievement gaps were eliminated (i.e., we've closed the gaps because everyone's doing equally poorly).  It challenged LEAs to evaluate their performance in locally determined, but comparable ways (i.e., it didn't mandate that everyone use the same standards or the same test, and it didn't impose definitions or criteria for proficiency).

NCLB was/is far from perfect, but it played a powerful (and I think positive) role in framing metric establishment activity regarding achievement levels, teacher quality, and acceptable assessments.  Panic ensued and implementation often went awry, but that wasn't entirely the fault of the legislation.