Superintendent Todd Cummings said in a statement the visit was unauthorized.
“Policies, protocols, multiple perspectives, and parent notifications need to be followed to ensure the continued trust of our families,” Cummings said.
District spokeswoman Susan Guibert declined to name the teacher.
A message from Cummings will be sent to families, Guibert said.
A spokeswoman for the Indiana Department of Education said the agency does not provide formal guidance for such situations and considers it a local matter.
Jackie Appleman, executive director of Right to Life Michiana, said her organization tailored its presentation for a public school visit and did not promote any religious or moral views.