One of the major problems in preparing the study of biology, especially about vegetation is the lack of real - samples. For instance for schools in the Northern Hemisphere it will be quite difficult to present vegetation samples from a tropical forest and vice versa.  which can be done by all students  age group. By using this technique it is possible for school partners from different part of the world to exchange these vegetation sample (mainly leaf) in the form of their "fossils" which can be transported and stored more easily.