(IES) Thinking Like a Scientist Lesson

Thinking Like A Scientist

Image of Thomas Edison. Black and white photo of him sitting in a chair. The inventor Thomas Edison once said that he never failed; he just found 10,000 ways that did not work. When you state a hypothesis, design an experiment, and test that hypothesis, you are engaging in science. Learning your hypothesis was wrong is a great success!! Now you know the hypothesis is wrong, and you can create a new hypothesis to test.

What is Science?

  • Science is a way of learning about the natural world and the knowledge gained through that process.

  • Scientists use scientific processes to study the patterns of natural events and to solve problems.

  • Scientific inquiry involves how scientists think as well as the techniques they use.

When you study science, you must think like a scientist. You have probably practiced some scientific thinking before.

Here is an example:

Jacob observes that the sky is dark with heavy clouds, so he infers that rain is coming and gets his umbrella

Observation involves using touch, sight, hearing, smell, and sometimes taste to gather information.

Never taste anything in a science lab unless you have been specifically instructed to do so.

An inference is an interpretation based on your prior knowledge and observations.

It is important to understand the difference between making an observation and inference.

Let's look at these terms further.

Observations

Observation is the gathering of information using our five senses or tools to extend the senses:

  • Sight

  • Smell - (waft technique)

  • Hearing

  • Taste (Only when safe)

  • Touch

There are two types of observations

Types of Observations

Qualitative

Quantitative

Qualitative observations describe what is observed.

"Qualitative" = quality (descriptive)

Qualitative observations use adjectives to describe observations and record data.

Ex: The flower has soft petals.

Ex: The dog is very excitable!

Quantitative observations measure what is observed.

"Quantitative" = quantity (numbers)

These observations use numbers to record data.

Ex: The flower has seven petals.

Ex: The linebacker weighs 212 pounds.

Inferences

Inferences are reasonable conclusions drawn from observations!

More Examples

Observation #1:  The grass on the school's front lawn is wet.

Possible inferences:

  • It rained.
  • The sprinkler was on.
  • There is dew on the grass from the morning.

 All of these inferences could possibly explain why the grass is wet.

Inferences are based on prior experiences. We have all seen rain, sprinklers, and morning dew.

Observation #2: The school fire alarm is going off!

Possible inferences: 

The school is on fire.

We are having a fire drill.

A student pulled the fire alarm.

The cooks burned dinner and there is smoke!

Each is a logical, reasonable explanation for why the fire alarm is going off.

Using Qualitative Data in a Science Experiment

Both types of observations are valuable in science.  However,  in an experiment, quantitative observations can be precisely and objectively compared.

  • Qualitative: The road is very long. (describes)
  • Quantitative: The road is 3 km long. (measures)

Scientists use innovative ways to convert qualitative observations into quantitative observations.

Converting Qualitative observations into Quantitative data

Example:  Your big, dead fish is smelly, but how can this smell be measured?

How would someone else know how smelly the fish actually is?

To solve this problem scientists would make a scale for "smelliness".

What about using a scale from 0-5. with a 5 as Nauseating and a 0 for no smell at all.

This would allow people to compare how smelly your fish is compared to others!

Doctor's and nurses sometimes use images to convert qualitative data, especially when working with children or when working with people who speak a language other than English. For instance, they may use the Wong-Baker FACES Pain Rating Scale. 

6 faces labeled 0-5

0 = Very happy, no hurt

1 = Hurts just a little bit

2 = Hurts a little more

3 = Hurts even more

4 = Hurts a whole lot

5 = Hurts as much as you can imagine (Don't have to be crying to be in this much pain) 

When a doctor uses this scale they would first describe each face and the meaning, then ask the person or child to point to the face that best describes their own pain.

 

[CC BY 4.0] UNLESS OTHERWISE NOTED | IMAGES: LICENSED AND USED ACCORDING TO TERMS OF SUBSCRIPTION