>> reporter: so two years ago, republican state senator peggy lehner put a wall around fourth grade, passing legislation that promised to hold back any third grader who failed the state's reading test. ohio called it the third grade reading guarantee. >> it's now or never. we're finished with passing kids along that are unable and unprepared to actually reach success at the higher grade levels. >> reporter: at the outset, third-grade teacher linda hissett of carson elementary in cincinnati welcomed the guarantee, and saw it as a solution. >> i had some students who were at a kindergarten-level reading first-grade-level reading, second grade. you know, i guess, i just, i look at it with dismay. >> reporter: but carson's principal, ruthenia jackson, was wary of the guarantee. some 40% of her students were in danger of being held back. >> the research shows that if you retain children over, it does not help them down the line, because they're just getting older, and then eventually...