Aim: How do scientists make observations?

Do Now: Write down five (5) things you notice about this classroom.

Observations

• Using one or more of your senses to gather information about the world.

• There are two types of observations (qualitative and quantitative)

Qualitative Observations

• Descriptions that DO NOT use numbers. Examples:

The sky is blue. The air smells good. Lemons are tart. The band is loud. The soap is slimy.

Quantitative Observations

• Descriptions that DO include numbers. Usually these observations are made using tools. Examples:

There are 26 people in the room. The football field is 100 yard long. The stone weighs 10 kilograms. The bottle contains 1 liter of water.

Tips for making observations:

• Use the five senses when it is safe (NEVER TASTE OR SMELL AN UNKNOWN).

• When possible use an instrument to make a quantitative observation. Make sure you include the unit of measurement.

• Check to make sure you are making statements about information gained through your senses and not explanations of what you observed.

What is an inference? • An inference is an explanation or interpretation of

observations. • Inferences are based not only on observations but

prior knowledge as well. Example: Observations made:

1. The tree is lying on the ground. 2. There is a saw next to it.

Inference: The saw was used to cut down the tree.

Activity

Use your knowledge of making observations to help you answer the questions on the sheet you were given.

Homework