This demonstration reinforces the concept that minerals can form even at low temperatures, meaning that these processes can occur at or near Earth’s surface. Using ‘water glass’ (sodium silicate nanahydrate) and any of a variety of metal salts, the teacher can grow crystals of silicate at room temperature in a container as the students watch and record their observations. A student worksheet and discussion questions are provided.
Biological weapons are defined as microorganisms that infect and grow in thetarget host producing a clinical disease that kills or incapacitates the targetedhost, or products of metabolism (usually, but not always, of microbial origin)that kill or incapac
In this activity students examine the effect of various levels of ground shade on new seedlings. They will build a model of a variable canopy out of a plastic grid. This activity offers students an opportunity to germinate seeds and maintain seedlings within a structured and controlled environment, an opportunity to observe how a canopy affects seedling growth, and an inquiry experience in which students compare and contrast the effects of canopy coverage on seedling growth.