What a difference a year makes.

PS 195 in Queens was rated with a D and ranked in the bottom 10 percent of elementary schools in 2010.

But after its students’ reading scores on state tests jumped 9 percent and their math scores 5 percent, the Rosedale school now ranks in the top 20 percent of city elementary schools.

It’s also one of just three schools to vault three letter grades, all of them from D to A.

“I had no idea this school received such a bad grade before — it really doesn’t deserve it,” said mom Helen Thompson, 40. “This is a great school with great teachers who care about our kids.”