COLUMBUS, Ohio (AP) — The struggle over what American students learn about global warming is heating up as conservative lawmakers, climate change doubters and others attempt to push rejected or debunked theories into the classroom.

An overwhelming majority of climate scientists say manmade emissions drive global warming, but there's no such consensus among educators over how climate change and its causes should be taught.

Several U.S. states recently considered measures allowing or requiring teachers to present alternatives to widely accepted viewpoints on such topics. For example, a stalled p...