How Do I Give Authentic Assessments? The Lab Practicum

I’m planning to have a lab practicum in which my students have to work in teams of three or four to figure out the composition of three mystery liquids (water, salt water, and rubbing alcohol). The content goals of this practicum is for my students to apply their understanding of boiling points (that boiling point is a characteristic property of matter), of lab safety, and of separating solutions. To receive full credit, students will need to be able to demonstrate that they can:

  • identify substances based on boiling points
  • separate a substrate from a solution and accurately calculate the concentration of substrate in the original solution (Each lab group will have to turn in a vial of salt that they’ve separated from the salt solution. Points will be given for accuracy of concentration calculation.
  • act in accordance to lab safety rules at all times (wearing googles, lab aprons, tying hair back, wearing gloves, turning hot plates off, etc.)

My students are already familiar with and have practiced all of the above steps in teacher-guided labs. We will also practice all these skills (particularly the safety related ones) whole-group before they start on the practicum. I have full confidence in their ability to perform.

However, I’m struggling with how to ensure that all students are active participants in this activity and with how to structure the practicum for and to teach good collaboration skills. For example, how do I make sure one student doesn’t dominate the group, or that another student just sits back and lets everyone else do the work? How do I teach students to productively work through disagreements, and how to exchange ideas and divide up work?

Questions that I would love your input in are:

  • What are “real” lab roles that you have as a scientist? Is there a materials manager? A safety monitor? Lead researcher?
  • What were your own experiences like working in teams?
  • What are skills that you utilize to collaborate with others that my students will need to learn and internalize to be successful?
  • How do I keep all students accountable for their content knowledge?
  • How do I teach students to mediate conflicts and disagreements?
  • How do I make sure all students are safe at all times?
  • Am I missing any questions that I should be asking?

Thank you so much in advance for considering this with me for my fifth grade scientists!