Viscosity Races

During our study of volcanoes, viscosity became an important word in each sixth grader's vocabulary.  In order for students to have a good grasp on how viscosity is a property used to describe liquids, we hosted Viscosity Races!  After introducing the word and discussing some examples, I gave students a list of materials that would be available to them during this lab.  Students worked with a buddy to brainstorm a procedure the class could use to compare the viscosity of various liquids.  After working in pairs, we discussed our ideas as a class and agreed on a procedure.  The next day, students worked in groups of four and were given four liquids.  They worked together to build a ramp and have the four liquids "compete" in a viscosity race.  Below are some pictures and the guided lab I used.

Illinois State Standards:

11.A.3a  Formulate hypotheses that can be tested by collecting data.

11.A.3b  Conduct scientific experiments that control all but one variable.

11.A.3d  Explain the existence of unexpected results in a data set.

11.B.3b  Sketch, propose and compare design solutions to the problem considering available materials, tools, cost effectiveness and safety.

11.B.3e  Evaluate the test results based on established criteria, note sources of error and recommend improvements.

12.C.3b  Model and describe the chemical and physical characteristics of matter (e.g., atoms, molecules, elements, compounds, mixtures).

Objectives:

Students will:

-design a controlled experiment

-create a data table to record results of experiment

-identify possible sources of error 

-compare the viscosities of various liquids

Assessment:

Students were assessed based on their data collection, analysis, and conclusion in their lab report.  Students were required to identify two possible sources of error, identify two ways to improve their experiment, explain how the different viscosities affected the results, and confirm or disprove their hypothesis.