Rainwater Vs. Tap Water
Fourth graders can easily learn the value and enjoyment that comes from scientific discovery. Teachers are encouraged to conduct simple experiments inside the classroom or science laboratory to convince students to participate. Later on, they should encourage their students to join science fairs that will show off their projects and their scientific prowess. The following are some experiments that 4th graders should find interesting. Rainwater vs. Tap water One experiment that can help interest 4th Graders is discovering the difference between rainwater and tap water. This type of query can involve chemical analysis of rainwater and tap water. Children can be asked to list down what chemicals they found in the rainwater and tap water. On the other hand, the boiling point of rainwater and tap water can also be compared through an experiment. To do this, rain water and tap water must be boiled in two separate containers. A thermometer must be placed in each. The temperature at which the water starts boiling should be recorded and compared, and the reasons for the results should be explored. Rain water and tap water can also be compared according to their contribution to plant growth. That is, which helps plants grow faster and better? For this type of experiment, two seedlings (same kind) should be planted. Everything about the two should be kept the same or controlled (e.g. the amount of sunlight received, the amount of water received, the soil type, etc) but one should receive only rain water while the other should receive only tap water. The plants' progress should be checked periodically and the results (height, leaves' colors and other plant health indicators) should be carefully recorded. Salt Water and Floating Objects An interesting way to demonstrate how salt increases the density of water is by conducting an experiment that illustrates how increasing the amount of salt in the water also makes it more possible for objects to float on its surface. It should be established from the start that an object floats on water whenever it is less dense than the water. To perform this experiment, the students should have various objects for floating. The dimensions and weight of these objects should be recorded. Then, start floating objects (preferably from the least dense to the most). Add salt to the water until the object floats and record the amount of salt it took to make each object float.
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