This document introduces fifth-grade children to the microscopic world, to the instruments needed to make it accessible, and to the appearance and structure of cells in nonliving as well as living things. Aims of the unit include providing children with an instrument which extends their senses in a radical manner, and leading them in using this instrument to see for themselves a much smaller level of organization of living and sometimes nonliving matter. The work is planned in such a way that children can discover for themselves whether the divisions they see in, for instance, an onion skin are found in everything or just in living things. Lesson topics include: liquid magnifiers; introduction to the microscope; onion cells; and epithelial cells. Background information for the teacher is provided along with an introduction to each activity. Types of related materials include correlation of objectives with several texts, available audiovisual materials, reference books, and suitable vocabulary. (MVL)