Former House Speaker Newt Gingrich defended President Barack Obama’s scheduled speech Tuesday to schoolchildren even as conservative voices across the country criticized it as an indoctrination effort.

“I have been in communication with Arne Duncan and the team at Department of Education,” former House Speaker Newt Gingrich said on "Fox News Sunday." “I believe this is going to be posted. People are going to see it in advance. It is going be a totally positive speech. If that is what it is, it is good to have the president of the United States saying to young people across America stay in school and do your homework. It’s good for America.”

Duncan's department is taking heat for proposed lesson plans distributed to accompany Tuesday's speech. Duncan acknowledged Sunday that a section about writing to the president on how students can help him meet education goals was poorly written and has been changed.

Duncan said viewing the speech is "purely voluntary." And he says the hubbub is something "I frankly don't pay any attention to."

Senate Republican Conference Chairman Lamar Alexander of Tennessee, a former education secretary under President George H.W. Bush, also backed Obama, according to Politico: “Of course, the president of the United States should be able to address students.”

Parents and teachers should be able to choose whether to show the speech, Alexander said. But it is a good opportunity to give students a civics lessons, he said, and teachers should embrace the moment by showing clips of other presidents.