I created this assignment for my 7th grade life science class but it could easily be adapted for upper or lower grades. The assignment consists of three parts.
First students organize and graph a list of mammals in order of shortest to longest gestation (length between fertilization and birth) period.
Second, students are asked to add Marsupials (mammals that raise their young in pouches) to their graph and compare their gestation lengths and reach some conclusions.
Finally, Students are given a writing assignment, where they are given a marsupial to research and summarize.
Great assignment that includes both a graphing and writing element!