We use the experimental cycle to help us plan, carry out and write about scientific investigations.

         Adapted from the IB MYP Sciences Guide

Inquire

Outline the problem or question to be tested

  • I want to investigate....
  • This is because I have observed that…

       OR

  • I will test the effect of ... on ....
  • This is because I have observed that...

Outline a testable prediction using scientific reasoning

  • I predict that...
  • This is because...
  • Other information that supports my hypothesis is....
  • My prediction is / is not testable. I know this because ....

A scientific problem is a question that we are trying to solve by making a hypothesis and testing it with an experiment.  

Design

Outline how to manipulate variables and how to collect data

  • The independent variable is the variable I am changing.
  • My independent variable is...
  • I will change the independent variable by...
  • The dependent variable is the variable I will measure.
  • My dependent variable is...
  • I will measure the dependent variable by...
  • I will repeat my measurements ... times to be more reliable.
  • The controlled variables are variables that I will keep the same to make my test more reliable.
  • I will control .... by...  because...

Design a safe, logical and complete method

  • There are some / no risks in this investigation because...
  • I will stay safe by ...         I will keep others safe by ...
  • I need to use these materials and equipment in my investigation...
  • I need to carry out these steps in my investigation...
  • This is a photo / diagram of my investigation

SAFETY FIRST!

Source: 4vector.com

Process

Collect, organize and present data

  • This table shows my measurements.
  • This graph shows my results.
  • I made these observations while carrying out my experiment...

Interpret data and outline the results using scientific reasoning

  • I think my data were / were not reliable because...
  • My data show that ....
  • My data suggest that ...
  • This might be because ...
  • Another source that supports this reason is... which says...
  • I conclude that this experiment has / has not helped me solve my original problem. This is because...

Tables and Graphs

We use tables and graphs to communicate our data clearly to others.

We will learn how to choose and use different types of charts and graphs to best tell the story of our data.

Reliability means how 'trustworthy' you think the data are.

 If you repeated your measurements did they give similar answers (reliable) or were they spread apart (unreliable)? 

Evaluate

Outline the validity of the prediction

  • I predicted that ...
  • My data support / do not support  /partially support my prediction.
  • I think this because...

Outline the validity of the method

  • My method did allow / did not allow / partially allowed me to answer my research question.
  • I think this because
  • Some strengths in my method were...
  • Some weaknesses in my method were...
  • Something I found difficult in carrying out my method was...
  • If I wanted to test the same problem again, I would / would not use the same method. This is because...

Outline improvements or extensions to the method

  • I could improve the method by ....
  • I would make these improvements because...
  • This investigation has made me think of a new question, which is...
  • I could test this by...
  • I would like to find out more about ... because...

"Banned words" list

  • "Proves"
  • "Correct"
  • "Right"
  • "Wrong"

These are not scientific.

Instead we talk about how the evidence we collect (our data) do or do not support our hypothesis.

Good scientists 

are not trying to 'prove' themselves 'right'.

Good scientists want to test their ideas in case they are not supported. This gives them more interesting questions to ask next

Commonly-confused words. Make sure you use them correctly. 

Facts

are simple truths that we use when we describe the universe. Often we can measure them.

  • "The Sun is hot."
  • "A pen falls if I drop it."
  • "Plants need water."

Hypothesis

is a testable prediction that we make, with a logical reason.

"I predict that the longer I leave my drink outside, the more ice will melt. This is because the ice is absorbing more energy from the Sun."

Theory

is our 'highest form of certainty' in Science, used to explain complex ideas. We can only call something a theory if it has been tested and tested and has not been disproven yet. The Theory of Gravity explains why objects fall towards Earth, for example.

(CC) Stephen Taylor (@sjtylr) i-Biology.net, based on MYP Sciences objectives (IB, 2004)