WHAT IS SCIENCE? Science is… A way to provide explanations and make predictions about the natural world. Always changing. A way of learning about the world around us. The knowledge gained by scientific studies over the years. Understanding what we know as well as understanding what we do NOT know.

The Scientific Method We use scientific thinking every day. It is a way to solve problems. The Scientific Method includes several steps.

Step 1: Observations & Questions We make observations using one of our 5 senses in order to ask thought-provoking questions. These observations and questions come from curiosity, skepticism, and creativity.

LET’S TRY IT: THE OBSERVATION: A woman leaves home and makes three left turns. She returns home again. On the way, she passed two people wearing masks. Who were the two people? THE ANSWER: The umpire and the catcher. THE FALSE ASSUMPTION: The woman was walking on city streets. She actually is on a baseball field.

It is a hot, August afternoon It is a hot, August afternoon. The location is the living room in an old Victorian mansion. The 7-foot window is open and the curtains are blowing in the breeze generated by the thunderstorm that just passed. On the floor lie the bodies of Bill and Monica. They are surrounded by puddles of water and broken glass. Neither Bill nor Monica have any clothing on. Picture the scene. How did Bill and Monica die? The Answer: They suffocated. The storm winds blew open the window, which knocked their fish bowl off the table, and it crashed onto the floor. False Assumption: That Bill and Monica are human. They are actually goldfish. Observation #2

THE OBSERVATION & QUESTION: You have observed there has been a decline in the frog population. What has caused this decline to take place?

Step 2: Forming a Hypothesis An inference is a logical interpretation based on what scientists already know. -Seeing umbrellas and assuming rain. Inferences can lead to a hypothesis, which is a scientific explanation for a set of observations that can be tested.

How do I tell the difference between an observation, an inference, and a hypothesis? An observation is using our 5 senses to take note of things around us. An inference is the conclusion drawn out from the careful watching and previous knowledge. A hypothesis is a testable idea formed from the observation

THE OBSERVATION & QUESTION: You have observed there has been a decline in the frog population. What has caused this decline to take place? INFERENCE & HYPOTHESIS: You make an inference that pollution may be a factor. You hypothesize that acid rain is causing a decline in the frog population

Step 3: Designing Controlled Experiments Testing a hypothesis involves designing experiments that keeps track of factors that can change, variables. Variables include: temperature, light, time, and availability of nutrients. If possible, only one variable should be changed. This is called a controlled experiment.

Variables Independent Variable: The variable that is deliberately changed. This variable is also called the manipulated variable. Dependent Variable: The variable that is observed and changes in response to the independent variable. Also called the responding variable. All experiments should have a control group.

THE OBSERVATION & QUESTION: You have observed there has been a decline in the frog population. What has caused this decline to take place? INFERENCE & HYPOTHESIS: You make an inference that pollution may be a factor. You hypothesize that acid rain is causing a decline in the frog population DESIGN AN EXPERIMENT: Taking water samples at various times of the year to determine acidity.

Step 4: Collecting and Analyzing Data Scientists make detailed records of experimental observations, gathering information called data. Two main types of data: Quantitative: numbers obtained by counting or measuring. Qualitative: descriptive, involves characteristics that cannot be counted or measured.

THE OBSERVATION & QUESTION: You have observed there has been a decline in the frog population. What has caused this decline to take place? INFERENCE & HYPOTHESIS: You make an inference that pollution may be a factor. You hypothesize that acid rain is causing a decline in the frog population ANALYZE THE DATA: From the water samples, determine the amounts of acid in the pond at various times of the year. DESIGN AN EXPERIMENT: Taking water samples at various times of the year to determine acidity.

Quantitative or Qualitative?? A: Quantitative B: Qualitative ___1. Number of frogs/square foot of pond ___2. Noting that frogs have a darker underbelly. ___3. Observing that the grass is not growing in some areas. ___4. The acidity of levels after rainfall. A B B A

Step 5: Drawing Conclusions Data is used to support, refute, or revise the hypothesis that is being tested. Many experiments may be needed to support one hypothesis. (Replication Studies) Peer review and sharing knowledge

Step 6: Communicate Results After an experiment has been conducted and it supports the hypothesis, scientists must report their findings for peer review and replication. After many experiments and many hypotheses, scientists may propose a theory that ties everything together. A theory is a well-tested explanation that joins a broad range of observations and hypotheses.

THE OBSERVATION & QUESTION: You have observed there has been a decline in the frog population. What has caused this decline to take place? INFERENCE & HYPOTHESIS: You make an inference that pollution may be a factor. You hypothesize that acid rain is causing a decline in the frog population ANALYZE THE DATA: From the water samples, determine the amounts of acid in the pond at various times of the year. DESIGN AN EXPERIMENT: Taking water samples at various times of the year to determine acidity. DRAWING CONCLUSIONS: Enough acid rain will limit egg development.

Spend this time reviewing vocab from this week… Bell Work Spend this time reviewing vocab from this week… Science Observation Inference Hypothesis Controlled Experiment Independent Variable Dependent Variable Control Group Data Quantitative Qualitative Theory Independent vs. Dependent Variables video https://www.youtube.com/watch?v=aeH1FzqdQZ0