WHO TEACHES THE TEACHERS:

Despite research that says one-time workshops and short-term training sessions have poor track records for changing teacher practices, they continue to be the most common form of professional development -- even now that the Common Core is supposed to be upending the old way of doing things, says Gulamhussein. While 90 percent of teachers participated in short-term training, just 22 percent observed classrooms in other schools, according to a 2009 study published by Learning Forward (formerly the National Staff Development Council), an international organization focused on increasing effective teacher training. Furthermore, the same study found that fewer than half of teachers who participated in training considered it useful. Still, districts shell out money on professional development, as much as 5 percent of the total budget in some places before the recession. Districts also get financial help for this purpose from the federal government and spent more than $1 billion in federal funds on such training in the 2012-2013 school year. Boston's education department spent about $5.5 million on professional development in fiscal 2014, up nearly $500,000 from the previous year, according to documents the district publishes online. Officials say additional money is allocated for teacher training from other areas of the budget.

Experts argue that this much is clear: If the Common Core is going to live up to expectations, teacher training needs to change, and fast.

THE COMMON CORE State Standards, created in response to American students' poor standing on international academic tests and applicable to public schools only, are a set of rigorous math and English Language Arts benchmarks that spell out what skills students should be able to perform every year from kindergarten through 12th grade. The goals do not tell teachers what materials to teach, but seek to make sure that kids leave every grade able to perform the same skills across district and state lines.

More than 40 states, Washington, D.C., and four territories voluntarily adopted the standards, which were created by education experts with assistance from teachers. Massachusetts already had high standards after major bipartisan school reforms in 1993. Nearly half of the state's fourth-graders are proficient on National Assessment of Educational Progress reading tests, and 55 percent of eighth-graders earn proficient scores on math tests -- the highest rates in the country. But because teachers here are still no closer to closing the achievement gap between wealthy and poor students than educators elsewhere, the state adopted the Common Core standards in 2010.

While the Obama administration did not have a hand in creating the Common Core standards, it has endorsed them and linked federal Race to the Top aid to "college- and career-ready" standards, which most states have interpreted as Common Core. To keep receiving aid, Common Core states must test students on the new standards beginning this school year. States were allowed to choose between two exams, the Partnership for Assessment of Readiness for College and Career (PARCC) and Smarter Balanced, or they could alter their own tests to meet college and career readiness standards. In Massachusetts, districts can choose between PARCC's test and the old Massachusetts Comprehensive Assessment System (MCAS), which has been aligned with the Common Core.

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