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Students will be able to devise 3 experiments for plant growth, based on prior knowledge.

Big Idea

This lesson is designed to guide students through developing a controlled investigation and making them aware of changing variables.

Note To Reader

2 minutes

As you read some of the resource materials in this lesson, you will notice they take on a "Detective/Mystery" feel.  This is because our classroom theme this year is the "Diligent Detective Academy".  Our entire year will revolve around solving mysteries in every curricular area, finding evidence to support claims, and presenting data to convince others. Therefore, I will be trying to act out the theme whenever possible!  I have added the Top Secret welcome letter to this lesson, just for fun.  It was mailed a week before school began, in order to excite the students and engage them in our first week activities.  


5 minutes

To engage the students today, I will display an announcement on the board, which states that our class will receive seeds in one week.  Our challenge will be to somehow get them to grow as well as possible.  

Here, I will prompt them to turn and discuss with their partners what they already know about seeds and about growing seeds.  This is not the time for me to teach the concepts of plant growth, as we will cover that when the seeds do arrive.  Today is about using prior knowledge in order to develop experiments in order to obtain new knowledge. 

After the students give me the thumbs up signal, I will ask them what they might know about plant growth and seeds.  As they speak, I will record their thoughts on the board. If they don't come to warmth (many will say sun), water, and space (or soil for a plant), then I will prompt them until it is on the board. I will then tell them that these will be our assumed 3 needs for seed to germinate. 

This YouTube video shows the elements nicely.  I will show it for a bit of background knowledge.

Our question to test is "How can we test these three elements to determine what is most important for a seed to germinate (begin to grow)."

Mini Lesson

12 minutes

My instruction will begin here, along with modeling.  I will show the students the Your Mission graphic organizer and explain that scientists must only test one thing (variable) at once.  Otherwise, outcomes can't be measured accurately, as the scientist can't know what caused the change.  

You may want to give a real life example that students can understand here.  For instance, the Michigan State Spartans finally won a game!  During that game, there was a new quarterback and the other team had two of its starters out due to injury.  How do we know why the Spartans won?


The MSU Spartans won. During that game, their new quarterback threw 4 touchdowns.  Why did they win?

Next, I will talk out loud through the process of thinking of an investigation that changes one or more variables.  As I fill in the chart, I will ask students if I am only changing one variable or more. My chart might look like this model.  The highlighted words show that there is more than one variable being tested. 


Active Engagement

25 minutes

As the investigative teams assemble and begin to debate experiments, I will circulate the room and listen in.  Here, I will be prompting students to only test one variable at a time, and watching how well they fill in the graphic.   This is the very beginning of our journaling lessons.  As time moves on, I will not supply them with as much organization. 

While you are circulating, listen for important communication skills, such as : If we do….then…will happen because…. or I think….because….Making sure students are explaining their reasoning, rather than just arguing their ideas is really important and crucial to the building of your science community.  

This video shows an example of a student working towards being more detailed with their investigation plan.  It is critical to work with students on realizing that others can not see into their heads!  They must be diligent in their descriptions of an investigation so that others would be able to carry it out.

I will also carry this Science Notebook Criteria - NGSS to help me identify areas of need.  Today, this form will be just for me to focus on skills and strategies.  In the near future, I will be sharing this document with the students, on piece at a time, as a focus for the day's session.  Each of these areas requires constant practice and opportunities, so be sure to look at it as a yearlong document. 

Sharing and Close

10 minutes

In order to share today, I will ask teams to pair up and discuss the experiments they devised and why. I will then ask the team partnerships to decide on the top two experiments out of all those discussed. They will write these ideas on post-it notes (one experiment on each) and place them on the board at the front of the room. This type of activity promotes debate in the classroom, which increases thinking and communication of claims based on evidence. 

Then, we will assemble at the community area and review these tests. I will complement the science practices as I hear/see them and prompt thinking to revise misunderstandings.