LANSING, Mich. (AP) — Michigan Gov. Rick Snyder has signed into law an early literacy bill that requires that third-graders be held back if they lag in reading, unless they qualify for an exemption.

Snyder signed the legislation Thursday. The Legislature approved the measure last month, voting in mostly party-line votes in the Republican-controlled Legislature. Democrats were largely opposed.

Starting in the 2019-20 school year, third-graders will not advance unless their state reading score is less than a grade level behind, they show proficiency through an alternative assessment or they demonstrate mastery through work samples. Parents may seek a “good cause” exemption letting kids still be promoted to fourth grade.

The law requires schools to intervene early when students are having reading problems.

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