Science Labs in Primary School: Process Knowledge

Doing a science lab with younger children can be stressful even to think about. I have made the choice to avoid labs before because I couldn’t figure out  a way to do it without wanting to rip my hair out.

But as my own hair is starting to fall out of its own accord, I have learned how to make labs with primary students relatively painless and certainly useful.

As I see it, there are three key parts of a successful lab with any age of students, but these components are even more important for young learners: process knowledge, content knowledge, structure and routine. 

The First Key: Process Knowledge

Students must understand the process of science before they can reasonably perform a lab. This will look a bit different depending on the level you teach. But the overall ideas remain the same. Our students should be familiar with an appropriate version of the scientific method.

By appropriate, I mean that we can adjust it to our students. A seven year old doesn’t necessarily need to memorize every step in the scientific method. But the seven year old should understand the scientific method to be something along the lines of, “I use what I know to make a hypothesis. Then I test it. I write what happens. I test it again and write it down again. Finally I say why my hypothesis was right or wrong.”

Content Light On Purpose

When I am introducing the scientific method, I want my students to focus on the scientific method, not the “science content”. I go about this by doing what I call a “content light” lab. This is on a topic I am certain my students have good knowledge on. This allows them to better focus on following the steps of the scientific method without being distracted by complex procedures the experiment’s outcomes.

For example, I would not teach the scientific method with a chemical reactions lab. Mixing acids and bases is great fun, but it would not lead to a focus on the scientific method. Students would likely be distracted by the complex procedures and or the novelty of the experience.

Content Light Labs

For a content light lab, we take notes on one step of the scientific method and then we immediately apply it in short steps. One of my go to’s for this is a lab on gravity. My students already have background knowledge (Second Key), the testing procedure is simple, and it is fast. All of this works together to allow students to focus on the scientific method.


1a. Define background knowledge: what you already know about a topic
1b. What do you know about gravity? Jot down this info as a class below the definition

2a. Define hypothesis: Using what you know to to explain what you think will happen in a testable and repeatable way
(This takes longer as you have to explain testable and repeatable)
2b. If I drop ‘Object A’ and ‘Object B’ at the same height, then “Object A/B’ will fall to the ground at a faster/slower/same rate.
(Feel free to adjust how you require students to form their hypotheses. But I do recommend always writing them in the same format. This makes it easier for students to focus on the science, not the writing.)

3a. Define procedure: steps to perform the experiment
3b. Grab two objects (not a single piece of paper) and drop them from the same height, then record the results.

4a. Define test: Doing the experiment
4b. Perform the procedure

5a. And so on…

The most challenging part here is step 4b. This is where the lesson is most likely to crash and burn. The way you can avoid this is with the third key, structure and routine. I will write about this more in a future post, but in brief here is my advice.

Have students perform step 4b in unison by following your direction.
Ex: “Ok, grab the two objects you decided to test. Everybody ready? Ok, good. Now hold them up, make sure they are the same height. Now, when I say go, drop them. Ready? 3, 2, 1 Go!”

The Second Key: Content Knowledge
The Third Key: Structure and Routine

Teaching The Scientific Method: Hypothesis

If you teach primary science, you will inevitably find yourself teaching the scientific method.2013-updated_scientific-method-steps_v6

  1. Asking A Question
  2. Background Research/Knowledge
  3. Hypothesis
  4. Design Experiment
  5. Test and Retest
  6. Analyze Data
  7. Draw Conclusions
  8. Communicate Results

In order to teach students how to write a hypothesis, you must first give them background knowledge. This is imperative. Elementary students are, by definition studying elementary topics, even top students will have a relatively low level of background knowledge.

In short, you must plan out what your students will need to know before they begin a lab. What background knowledge do they need? How will you make sure they know it before the lab?

 After your students have made observations and obtained the necessary background knowledge, they can begin working on their hypothesis.

Hypothesis: An idea that helps you learn about the world that is testable and repeatable

I start by teaching what testable and repeatable are by using a seemingly ridiculous hypothesis. “If I let go of this pen, then it will go up because of the force of gravity.”

Students think it is funny because the hypothesis is obviously wrong. And I want them to know it is wrong! So I repeat the phrase, and let the pen go to test my hypothesis. Next, I ask my students what happened. Finally I repeat the hypothesis and experiment.

Then I ask, “Was the hypothesis testable?” and “Could I repeat the experiment?” And I follow that with, “Was my hypothesis correct?” 

This leads to something many students find counterintuitive. A hypothesis can be both valid and wrong. Over the course of a school year, I will repeatedly ask my students if a hypothesis can be wrong and be valid because it is important.

Writing A Hypothesis

Then, when we begin working on writing hypotheses. I teach my students to use the “If….Then…Because…” format. I always keep the format the same. This makes the scientific method easier to learn because this step is never changes and makes it easier for students to focus on the science content.

The Variables

Next, I teach my students about variables by writing the definitions and linking them to my hypothesis and the If, Then, Because format.

Independent variable: The variable you change
The ‘If’ statement identifies the independent variable/s (what the student changes).
Letting go of the pen is the independent variable.

Dependent variable: The variable you measure
The ‘Then’ statement identifies the dependent variable/s (what the student measures).
What happens to the pen is the dependent variable.

Next we go over the control variable.
Control variable: What you must keep the same
The height and force that the pen is let go with must be the same in every trial of the experiment.

The Reason

The ‘Because’ statement identifies the proposed reason “something” will happen. This should be based on their background knowledge that you have already taught them.
The force of gravity is the proposed reason.

Putting It All Together

The ‘If’ statement identifies the independent variable/s (what the student changes).
The ‘Then’ statement identifies the dependent variable/s (what the student measures).
The ‘Because’ statement identifies the proposed reason “something” will happen.

What I do in the next class is to have students practice identifying variables in various experiments. Generally, elementary students will be better at identifying control variables than discriminating between independent and dependent variables. That is fine. Expect them to struggle initially and give them regular practice. They will improve. You will improve in your explanations and examples too! Hypotheses are tricky. Work at them and practice it with your students.

Teaching The Scientific Method: Asking A Question

If you teach primary science, then you will inevitably find yourself teaching the scientific method.


  1. Asking A Question
  2. Background Research/Knowledge
  3. Hypothesis
  4. Design Experiment
  5. Test and Retest
  6. Analyze Data
  7. Draw Conclusions
  8. Communicate Results

Ask a question

It starts with a question, but a question is always preceded by an observation. This means that we must teach our students how to observe. Even though observations are simple, do not assume your students will understand it because you think it is easy. You will have students make unscientific observations. As a way to circumvent this, give your students a simple definition with simple rules to follow. Then give them both examples and non-examples.

Observation: Learning something with your sight, smell, touch, taste, or hearing.

Rules: Not an opinion. Not an inference.

Non-Example Example
“The ants want to climb the tree.” (inference) “The ants are climbing the tree.”
“The flower is beautiful.” (opinion) “The flower has a green stem and purple petals.”

Even with a simple, child friendly definition with simple rules to follow, you will still have students making inferences and creating opinions instead of observations. The only way to fix this is to explicitly model and explain how you make observations and then to give students lots of practice and feedback as individuals or groups.

One way to make their practice more effective can be to have students change an opinion or inference into an observation. For this, you will need to model and explain it first. Again, even if it seems simple to you, it isn’t for your students. If your students thought it was simple, they would do it and get it right.

With that being said, making observations are still simple enough for your students to learn relatively quickly provided they receive explicit modeling and practice with feedback.

Think about every single step you automatically take as you go through the scientific method. You will find that the scientific method is a simplification of the scientific process. Explain and model the little steps, not just the ones your scientific method poster lists on the wall.

To Recap, give your students…

  1. A child friendly definition
  2. Simple rules
  3. Both non-examples and examples
  4. A model on how to make observations
  5. Practice with feedback