Note: Each group of students should receive a set of seeds that do not have hard seed coats and seeds that do have hard seed coats. However, each group can be given different seeds so that scarification can be compared from group to group to determine the effects that scarification has on several different kinds of seeds. For example, group one may test green bean and mesquite seeds, while group two may test cucumber and sesbania seeds. Students may test more than just two sets of seeds if space is not limited. Or more seeds of the same sets can be tested.