Teamwork
Colorful Indicators

	Brief Description Objectives Materials and Resources Activity Description Internet Resources

• Grade level: Upper or Lower Elementary

• Subject Area: Science, Language Arts

Brief Description

    Students conducting the following experiment will learn about acids and bases by creating a solution to test for them and by using the Internet to ask questions of scientists and/or to conduct Internet-based research. Students can collaborate with students at other schools either by conducting the experiment synchronously over CU-SeeMe or by exchanging data, information, and observations over email.
Objectives

    Students will:

• use the scientific method to collect data.
• gain experience communicating scientific data.
• enhance their writing abilities by corresponding with an online scientist and sharing data with students at other schools.

    In developing our lessons and activities, we made some assumptions about the hardware and software that would be available in the classroom for teachers who visit the LETSNet Website. We assume that teachers using our Internet-based lessons oractivities have a computer (PC or Macintosh) with the necessary hardware components (mouse, keyboard, and monitor) as well as software (operating system, TCP/IP software,networking or dial-up software, e-mail and a World Wide Web client program, preferably Netscape, but perhaps Mosaic or Lynx). In the section below, we specify any "special" hardware or software requirements for a lesson or activity (in addition to those described above) and the level of Internet access required to do the activity.

1. Special software requirements: CU-SeeMe (optional).
2. Internet access: Medium-speed (28,000 BPS via modem), or High-speed (greater than 1 MBPS via network).

• chopped red cabbage
• knife
• bowl
• water
• lemon
• two water glasses
• cooking pot
• colander
• tablespoon
• baking soda

Pre-activity Preparation:

• Make cabbage water by heating the chopped cabbage and two cups of water in the pot for ten minutes, until the water is dark purple. Use the colander to strain the cabbage over the bowl and save the cabbage water for the experiment.

• Find a scientist who would be willing to field questions from students about acids and bases, either synchronously over CU-SeeMe or asynchronously over email. You might contact a scientist in your area who would be willing to correspond with students, for instance.

• Find a class at another school that would be willing to exchange data, either synchronously over CU-SeeMe or asynchronously over email. You might contact a school in the same or a nearby district, for instance.

Activity

• Add a tablespoon of cabbage water to a glass containing a tablespoon of lemon juice.
• Add a tablespoon of cabbage water to a glass containing a tablespoon of baking soda.
• Record your observations.
• Add cabbage water to other types of foods, such as fruit juice, egg white, or vinegar. Record these observations. Discuss with students which kinds of foods turn the cabbage water certain colors. What do foods that turn the water the same color have in common with each other? Have students heard of any natural phenomena having to do with acids or bases (e.g., acid rain)?
• Share data with students from another school over email and/or CU-SeeMe. Compare types of food tested and experimental results.
• Pose questions to a scientist about this experiment over email and/or CU-SeeMe. Conduct background research about the potential relevance to our lives of knowing about pH levels. Use the resources below and directed Internet searches.

• Determining Acids and Bases
  [http://unite2.tisl.ukans.edu/UNITEResource/783750699-447DED81.rsrc]
  This is an indicator activity from the Explorer database, a database of science activities and experiments maintained by the University of Kansas. The activity is downloadable in ClarisWorks or Acrobat format.

• You Can & Acid Rain
  [http://www.nbn.com/youcan/acid/acid.html]
  Another take on the indicator activity, this time in the context of acid rain.

• EcoNet's Acid Rain Resources
  [http://www.igc.apc.org/acidrain/]
  General information on acid rain.