Introduce the scientific method to your students through one of water’s most important properties; surface tension. In this lab students will learn to define and determine how water possesses the ability to stick to itself. Using the introduction background knowledge, students will develop a hypothesis as an “If... then…” statement that supports the experimental question of “How does soap affect the surface tension of water?”. Students will test their hypothesis by counting the number of drops that can stick to a single penny, first using water and then repeating the experiment with soapy water. After collecting their data, the results are shared as a class and used to determine the relationship between the number of soapy water drops and the surface tension.

Standards Covered:

• Learn to write a hypothesis as an “If... then...” Statement
• Test a Hypothesis
• Identify the Independent Variable, Dependent Variable, and Control Group
• Record Data
• Communicate and Compare Results among Classmate Groups
• Learn to Calculate the Average from a Set of Data

Materials Needed per Station:

• 2 Beakers
• 2 Pipettes or Droppers
• 1 Penny (1 per Student)
• Hand Soap (Color makes it Easier to See the Difference Between Water)
• Access to Water
• Paper Towels (Mess/ Wiping off Pennies in between)

Includes:

• Editable Data Worksheet
• Post Lab Inquiry Questions
• Easy Teacher Instructions