This 19 fact sheet curriculum series provides a series of individual lessons covering manatee biology and ecology, as well as highlighting some of the ways that humans impact and can protect manatees. The curriculum has been written at a third grade level but can be adapted for older or younger students. (Photo credit: Keith Ramos, USFWS)
http://edis.ifas.ufl.edu/topic_series_third_grade_manatee_workbook