House Bill 1266 was introduced in the Missouri House of Representatives on January 9, 2006. Dubbed the Missouri Science Education Act, HB 1266 would, if enacted, require public school science teachers in grades 6 through 12 to comply with a list of "best practices" in order "to support the truthful identity of scientific information and minimize misrepresentation while promoting clarity, accuracy, and student understanding" and "to support the objective teaching of scientific information and minimize dogmatism while promoting student inquiry, healthy skepticism, and understanding." The only topic explicitly identified as in need of such revisions is evolution; the bill provides that "If a theory or hypothesis of biological origins is taught, a critical analysis of such theory or hypothesis shall be taught in a substantive amount."
The sponsor of HB 1266 is Representative Robert Wayne Cooper (R-District 155), who in 2003 introduced two bills calling for "intelligent design" to be taught in the Missouri public schools. HB 911 would have required that, "[i]f scientific theory concerning biological origin is taught, biological evolution and biological intelligent design shall be taught and given equal treatment"; it also contained a provision that would have terminated the employment of teachers and administrators who failed to accord with the bill's dictates. HB 1722 would also have required "the equal treatment of science instruction regarding evolution and intelligent design". Both bills died in May 2004, when the legislative session ended.