The secret container
Tommie Zetterlund; Bromangymnasiet Hudiksvall
Target Group
16-18 years old students
Brief Description
In this simple yet intriguing introduction to science the students form hypotheses on how the secret container is constructed on the inside.


The secret container — an introduction to science

The secret container
is a perfect start to the course. It is a simple yet intriguing introduction to science and a natural science approach. The experiment is based on observations, and these then form the basis for student’s hypotheses.

This way of thinking about knowledge is often perceived controversially by the students. They think that "It's clear that you know". The secret container challenges students "truths" and perceptions about knowledge.

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Do this:

9k=1.  Prepare The secret container in advance without the students present. Attach the small pipe as illustrated in the PDF-file and fill the container with water up to the pipe. Secure the plastic bag firmly to the funnel and put the plastic bag in the container as illustrated above. Make sure that the plastic bag is not visible from the outside. Have The secret container visible to all and tell the students that they are not allowed to touch the container, or come close to look - they are only allowed to study it from a distance.

2.   Start the experiment with pouring water into the funnel. Clean water will then sip out of the tube. Instruct the students to work in groups and give them the task to figure out how The secret container is constructed on the inside.

3.     Have the groups draw their hypotheses on the board. Let them explain their hypothesis.

4.   Tell the students that you are about to pour a soda can (or coulored water) into the container and ask them what they think will happen. Start pouring the can into the funnel. Clean water will then sip out of the tube. Pause. Instruct the students to go back do the drawing board and draw how The secret container is constructed on the inside considering their new observations.

5.   Now the fun starts. Have the groups draw their new hypotheses on the board. Wild ideas come forth. Let them explain their hypothesis. Do not dismiss them without accepting them as the students' own hypotheses.

6.    Discuss in class! Discuss how the hypotheses can be tested through further experiments suggested by the students, such as other colors, pouring sand instead of a liquid etc. Discuss the importance of trying to falsify your own hypothesis and that you have to design experiments with that in mind. Discuss how many further experiments they think is needed to comfortably being able to say “Now we know!” (Without opening the container!). How do we know things in life? How do we know that a pen will fall to the ground if we drop it? How do we know that the laws of physics works? How do we know how things in life are without being able to open “The secret container of the Universe”?

IMPORTANT! NEVER reveal how The secret container is constructed! You
want the students to leave the classroom still curious of what’s inside it. The
secret of the container remaining hidden symbolizes that we can never “ask the
Universe” how things are. We have to repeatedly experiment to the point that we
do not need to “ask” to know! And we have to use reliable methods and have a
scientific approach for that to work.


Additional teacher's guide

The goal of The secret container is to reflect a science-based approach – it is through hypotheses and experiments that we draw conclusions about how things are! In addition it is important for the students to realize that there is no "complete answer”. The secret container is therefore intended to start a process in the minds of the students (provided that you do not reveal how The secret container is designed!).

I use The secret container as an introduction to the scientific method. It begins with a problem that causes one or more hypotheses, more or less qualified guesses, which are then tested through experiments. This leads to a result and a conclusion – either the hypothesis was true or false. The next step is to discuss the result, form new hypotheses and restart the process. Repeatedly tested hypotheses eventually become the body of scientific theories. This process will continue until someone succeeds in falsifying the theory or parts of it. If so, it's time to rethink it. It is important to point out that all new knowledge really is based on the fact that old hypothesis and theories are falsified, not that they are verified!

The scientific method


Suggestions on concept to discuss

·        Hypothesis – A more or less qualified guess

·        Scientific theory – The result of repeatedly tested hypotheses

·        Falsify – To invalidate or "show to be false"

·        Falsifiability – is synonymous to testability. The term falsifiability is used to distinguish science from non-science/pseudoscience. Statements, hypotheses, or theories have to have falsifiability. If not it is not science.

Related files

The secret container_ENG 373 KB
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