He is a prominent critic of creationism and intelligent design and an activist against campaigns of suppressing teaching of evolution and climate change in school education.

"[11] Branch was involved in the campaign against the Discovery Institutes' "Teach the Controversy,"[12] a challenge to the key principles of Darwinian evolution based on an annotated bibliography of 44 peer-reviewed scientific article which were said to raise doubts about Darwin's theories.

NCSE concluded that the only purpose of the Discovery Institute's Bibliography was to mislead members of the Board of Education and of the public about the status of evolution.

In an opinion piece written with Eugenie Scott, the coauthors stated that it "is scientifically inappropriate and pedagogically irresponsible to teach that scientists seriously debate the validity of evolution."

He believes one of the most effective ways to improve awareness of climate change is through school education by science teachers.

[1] An increase of bills aimed at changing standards for climate science education introduced by state officials in early 2019 has signaled concern.

[17] He attributes the resurgence of the movement to a YouTube video posted in 2011 entitled "The Globe Model Attempts to Deceive the Public."