An educational think tank says Kansas is replacing some of the nation’s strongest science standards for public schools with weaker, multistate guidelines.

The Thomas B. Fordham Institute’s report on the new standards was released Thursday, two days after their adoption by the Kansas State Board of Education.

The new standards were drafted by 26 states and the National Research Council. Educators and officials have praised them as a major improvement, partly because they emphasize hands-on projects.

But Fordham Institute gave the multistate standards a “C” grade.

And the institute last year gave Kansas’ old standards a “B.” Only seven states and the District of Columbia received higher grades.

The institute says the newest standards scrimp on detail about the key concepts students are supposed to learn.