6th Grade Science : Unit #7 - Physical and Chemical Changes : Lesson #4

Fishy Mixture Water Quality Inquiry Lab (Part 4/4)

Objective: SWBAT identify, classify and separate different types of mixtures based on physical and chemical properties of matter.
Standards: MS-PS1-2 MS-PS1-3 SP1 SP2 SP3 SP4 SP5 SP6 SP7 SP8
Subject(s): Science
60 minutes
1 Introduction - 0 minutes

The Fishy Mixture Water Quality Inquiry Lab is an inquiry project including multiple lessons taught over the span of 1 to 2 weeks. To help manage the magnitude of this project, you will find the project split into 4 parts.

  • Part 1 includes the ENGAGE and EXPLORE components of the lesson; Time: 2 - 3 50-minute lessons or equivalent block periods. 
  • Part 2 includes the EXPLAIN component of the lesson; Time: 1 50-minute lesson.
  • Part 3 includes the EXTEND component of the lesson; Time: 2 -3 50-minute lessons or equivalent block periods.
  • Part 4 includes the EVALUATE component of the lesson; Time 2 50-minute lessons or equivalent block period.
2 Next Generation Science Standards - 0 minutes

This lesson utilizes many of the Next Generation Science Standards. I've described how these standards are met in this video.


In addition, details of the alignments of content standard to concepts and practices are found in the resource Fishy Mixture NGSS Alignment.

3 Evaluate - 100 minutes

The purpose for the EVALUATION stage is for both students and teachers to determine how much learning and understanding has taken place. To accomplish this goal, we complete several activities:

1) We evaluate the water samples using the Fishy Mixture Water Quality Rubric (Water Quality Scoring Rubric Example). I often bring the samples up to the front and we evaluate the samples together as a way of sharing our data. During this time, we share what separation methods were successful and which were not. This video explains the evaluation of the water samples:


2) Students plan and write a RECALL Lab Conclusion (see these related lessons: Writing a RECALL Lab Conclusion Part 1 and Part 2) using the graphic organizer in the Fishy Mixture Lab Sheet. I often give students a choice about how they want to present this information: finalize their planning into a final lab report or finalize their planning into a final creative presentation (Prezi, Google slideshow, Infographic, Google poster). For examples of student RECALL Lab Conclusions, view these: Fishy Mixture RECALL Student Example 1, Fishy Mixture RECALL Student Example 2 and Fishy Mixture RECALL Planning Student Example. For writing rubrics, try: Scientific Communication Rubric or Argument from Evidence Rubric.

3) Upon completion of this project, a final class discussion using several prompts to assess what we have learned and think about next steps is an appropriate closing activity. These prompts may include:

  - What can you conclude about separating mixtures from this activity?

  - What do you think we should do to save the white sucker fish?

  - What other types of mixtures might be harmful to humans or the environment?

  - Whose responsibility is it to provide us with safe water?

Set a Real World Context
Problem-based Approaches

Students may get competitive during this step of the process. I make sure to reiterate that the scores they receive on their Water Quality Rubrics are a way of quantifying their results. I do play up the competition enough to keep the idea going that they are trying to save a fish species and that in real life, consultants can be hired and fired over results.

While I have students complete a formal lab conclusion or creative lab conclusion, there are many other ways of assessing student understanding. For example, I have played with the idea of having students make a final report and presentation. The reason I choose an individual assessment rather than a collaborative one is that students have worked together for the entire process. I want to know what they have learned individually.

The final discussion is important so that students make the connections one would hope they make. I hope they connect the essential questions and objectives from the unit to this lesson. I also hope students make the conceptual leap from an activity completed in a lab environment not only to science that occurs in the field, but to a greater understanding of connectivity of systems. This leads to fruitful revelations on how humans impact the environment and how, ultimately, the environment impacts us.