Set 4 Includes 3 Kits, The Bacteria and Fungi Kit, The Weight and Volume Kit, and THe Acids and Bases Kit. Bacteria and Fungi, Young Scientists of all ages will be fascinated by growing bacteria and fungi of all colors and textures in Petri dishes. They will discover how antibiotics cure disease. Young Scientists finish the kit by waking the common fungus called yeast. Weight and Volume, In this kit, Young Scientists learn about weight by making and calibrating their own spring scale. Students then learn about volume using a metric calibrated graduated cylinder. The concepts of weight and volume are combined to study density by making a peppercorn magically float. Acids and Bases, Young Scientists learn about acids and bases by testing various substances with pH and litmus paper. In addition, the effects of acids on various items around us are studied; e.g. dirty coins and rain. This kit finishes with some real copper plating. A great introduction to chemistry.