Clouds

Objectives

• Students will identify "ingredients" of a cloud. (Analysis)
• Students will determine if a given weather scenario is beneficial for cloud formation. (Comprehension)

Materials

• Glass jug
• Matches
• Weather book for each student

Procedures

1. Gather the students on the carpet area. Ask class, "What is a cloud?" Ask, "What are clouds made up of?" Let the class explore options and share ideas.
2. Explain to class that we will be making a cloud in the classroom. Ask the class to watch very carefully to what happens as the cloud is being formed and to pay close attention to the steps taken in forming the cloud. Turn the glass jug upside down and hold a lit match inside the mouth of the jug for about 5 seconds. Wait until the glass cools, then put mouth over the mouth of the jug so that it is completely covered. Blow hard and try to force some air into the jug. Ask class, again, to watch what happens carefully.
3. Ask students what happened and how. Ask class if anyone knows the "ingredients" to make a cloud. Have them list ingredients put in the bottle. Write the ingredients on the chalkboard as they say them. Urge students to speak amongst each other to solve the "problem".
4. When students have discussed all possible ingredients, tell them that one needs only two ingredients to make a cloud: tiny particles (soot in this case), and moist air (my breath). It is also necessary to cool both of these. In order to cool air, the pressure must be lowered (as learned in a previous lesson). Ask how the pressure was lowered in this example. If they cannot come up with the answer , explain that this was done by taking my mouth away. As a result of this, the air cooled as it rose out of the bottle. Make sure to explore all of the students thoughts before providing them with the "answers".
5. Have students volunteer to read the "Cloud" section of the weather book aloud.
6. Tell students that in class, the particles we used were soot. Ask students what types of particles are in the sky that would help form clouds? Ask what the purpose of the particles is?
7. Give the class scenarios and ask if a cloud would be formed in that situation. For example: complete dryness, dust and cool air. (NO) Some water vapor, volcanic ash and cool air. (YES) etc.

Evaluation

1. Can students come up with a list of "ingredients" for a cloud after observing the formation of one?
2. Did students answer "No" when given a weather scenario that was not conducive to cloud formation? Did they answer yes when it was?