Day 2-Is It Really There... Proving Salt Is In The Water

3 teachers like this lesson
Print Lesson


SWBAT prove dissolved salt is still present in water.

Big Idea

Students will use evidence from their investigation to construct a scientific explanation that salt is really in the water.

Lesson Overview

5e Lesson Plan Model

Many of my science lessons are based upon and taught using the 5E lesson plan model: Engage, Explore, Explain, Elaborate, and Evaluate. This lesson plan model allows me to incorporate a variety of learning opportunities and strategies for students.  With multiple learning experiences, students can gain new ideas, demonstrate thinking, draw conclusions, develop critical thinking skills, and interact with peers through discussions and hands-on activities.  With each stage in this lesson model, I select strategies that will serve students best for the concepts and content being delivered to them.  These strategies were selected for this lesson to facilitate peer discussions, participation in a group activity, reflective learning practices, and accountability for learning.

Unit Focus

The Matter and Energy unit focuses on the impact of temperature and pressure on solids, liquids, and gases. Students have multiple opportunities to develop an understanding that matter cannot not be created nor destroyed, only change. Through investigations of objects and substances, students  identify materials by their properties, states, and determine if changes made to them are physical and chemical. Additionally, investigations include identifying materials that dissolve, mix, and change form and create a new substance. Students demonstrate their understanding by developing and using models, planning and carrying out investigations, constructing explanations, and using mathematical and computational thinking.

Lesson Synopsis

The Day 2-Is it really there?...Proving Salt is in the Water, follows yesterday's lesson which had students design an investigation. Today, students work on constructing a scientific explanation on their investigation  . Students are provided a graphic organizer to help them process the content and concepts and make sense of their observations and outcomes. They use the graphic organizer to help them write  a scientific explanation. This is collected and used as an assessment.

Next Generation Science Standards  

This lesson will address the following NGSS Standard(s): 

PS 1-1 Develop a model to describe that matter is to small to be seen. 

PS 1-3 Make observations and measurements to identify materials based on their materials.

Why do I teach with this lesson?

I teach the "Day 2-Is it really there?...Proving Salt is in the Water" lesson to help my students develop scientific explanation writing skill. Many of my student have very limited background in science as the elementary school's within my district do not formally teach science prior to my students entering the 5th grade (the middle school). I find it important to provide guided inquiries that build their vocabulary and understanding of concepts in order to facilitate scientific thinking for future inquiry lessons. In this lesson,students reflect and write about their investigation to prove salt is really in the water even though it cannot be seen.  They use their design to show salt is really in the water and construct an explanation to that will support their experience on the investigation and outcome. 

Scientific & Engineering Practices

Students are engaged in the following Scientific and Engineering Practices

4.) Analyzing Interpreting Data: Students use a graphic organizer to help them analyze the evidence they collected during their investigation of proving salt was in the water.

7.) Constructing Explanations:  Students use their observations and investigation outcome to write a scientific explanation to support their conclusions and claim. This helps students further develop their ability to communicate information from collected observations and data.

Crosscutting Concepts

The Day 2- Is It Really There?...Proving Salt Is in the Water lesson will correlate to other interdisciplinary areas.  These Crosscutting Concepts include:

2.) Cause and Effect:  Students make a claim based on evidence to prove that salt is really in the water and justify why is appears unseen.

Disciplinary Core Ideas

Disciplinary Core Ideas within this lesson include:

PS1.A Structure of Matter:  Matter of any type can be subdivided into particles that are too small to see, but even then the matter still exists and can be detected by other means.  A model showing that gases are made from the matter of particles that are too small to see and are moving freely around in space can explain many observations.


Classroom Management Considerations

  • Importance of Modeling to Develop Student Responsibility, Accountability, and Independence 

Depending upon the time of year, this lesson is taught, teachers should consider modeling how groups should work together; establish group norms for activities, class discussions, and partner talks.  In addition, it is important to model think aloud strategies.  This sets up students to be more expressive and develop thinking skills during an activity.  The first half of the year, I model what group work and/or talks “look like and sound like.”  I intervene the moment students are off task with reminders and redirecting.  By the second and last half of the year, I am able to ask students, “Who can give of three reminders for group activities to be successful?” Who can tell us two reminders for partner talks?”  Students take responsibility for becoming successful learners.  Again before teaching this lesson, consider the time of year, it may be necessary to do a lot of front loading to get students to eventually become more independent and transition through the lessons in a timely manner.


For time management purposes, I use “lab rats roles” I introduce these roles this at the beginning of the year. I model each role and provide students' opportunities to practice each role with a group during an investigation or lab.  It has proven successful within my classroom keeping students engaged and on task.

Each student has a number on the back of his or her chair, 1,2,3,4 (students sit in groups of 4)and displayed on the board.  For each explore activity, I switch up the roles randomly so students are experiencing different task responsibilities which include: Director, Materials Manager, Reporter, and Technician.  It makes for smooth transitions and efficiency for set up, work, and clean-up. 


Engage and Explore

15 minutes

Today, I begin by directing the lab rats materials manager to retrieve their groups investigation materials from yesterday.  I ask groups to display their models and evidence that proved salt was really in the water in the center of the table.  While they set it up, I give each group a large piece of construction paper to place near their evidence models. 

Once groups have their materials on display, I engage them in a gallery walk to see how other investigations proved salt was really in the water. As students walk to each station, I ask them to write a positive comment, something they noticed or or learned from that group's investigation, and/or comment by writing it on the construction paper at that station. I want them to notice that their is more than one way to prove salt is in the water.

When the gallery walk is over, I ask students to return to their group where they are analyze the comments, questions, or observation.  I give them a few minutes to read and raise their hand if they can answer a question on their groups poster.

Elaborate and Explain

20 minutes

Constructing a Scientific Explanation

I have students locate the "Developing a Science Explanation" graphic organizer on page 4 of their investigation packet.  I point out each section of this organizer and explain to students what they are to do.  

developing a scientific explanation


I tell them to use the evidence they collected during their investigation to accurately fill out each section.  This graphic organizer is for them to focus on certain parts of their investigation and the observations they made.  I have my students use this to organize what they have learned so they can apply it to constructing an evidence based scientific explanation.

They begin by identifying the guiding question and explaining the investigation they created to answer the question: "Can you Prove Salt is Really There?

  • What is the investigation question?
  • How did you collect evidence to support your explanation?


Then, they move on to writing a claim statement followed by evidence to support their sentence. They refer back to their observation notes to use as evidence for this section of the table. Once they identify their evidence, they link their claim and evidence together to develop reasons for the outcome. In addition, I remind them that in this section they should apply what they already learned about matter throughout our unit: matter cannot be created nor destroyed, it can only change and the particle theory.  By connecting what they have learned already to their evidence in this investigation, my students are engaging in a higher level thinking to scientifically explain outcomes.

  • Claim: A statement that answers the question you investigated
  • Evidence that supports your claim -data and observations you collected during your investigation (Number each piece of evidence)
  • Reasoning: I think (insert your claim) answers the question because (links evidence to the claim)


At this point, I ask them to analyze the evidence they have collected.  I want them to develop an understanding that some evidence is stronger than others to draw a conclusion.  I have them write their analysis in the bottom half of the graphic organizer.

  • What do you consider the strongest evidence and why? 
  • What do you consider weaker evidence and why?


Once they have completed their graphic organizer, I take a look at it.

 develop a scientific explanation     developing scientific explanation


I want to make sure they are on track for constructing a scientific explanation about their understanding of this investigation.  I tell them to keep it out as a reference.


25 minutes

I bring students' attention to the last portion of the investigation packet.  I point out the directions: Write your scientific explanation. I also call attention to the equation at the top of the page: Scientific Explanation = Claim + Evidence + Science Reasoning. I review with them that a good scientific explanation incorporates many parts of the investigation including the planning, process, and evidence. I direct them to the different parts of the table on the graphic organizer:

I share that it is important to use their graphic organizer to help them write a well written explanation.  

Next, I hand out the rubric that will be used to score their scientific explanation. I review each component on it, noting the what each score means.


My students are familiar with rubrics, but I find they it necessary to review them for each assignment. I want my students to continue practicing using them to self assess their work.  

In addition, I provide them with a sentence frame to get started.  I find many students struggle with starting an explanation. By providing them with a sentence frame/starter, they can can focus their attention to writing.

Students work for the remainder of class time and are instructed to finish it for homework.  I collect them the next day and use as an assessment for this lesson.