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Science Starter August 16, 2013. Jared investigated chemical reactions based on smell, color change, and release of bubbles. What types of evidence would support any conclusion Jared makes? An observation An estimation A calculation A measurement
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Science StarterAugust 16, 2013 Jared investigated chemical reactions based on smell, color change, and release of bubbles. What types of evidence would support any conclusion Jared makes? An observation An estimation A calculation A measurement Don’t forget to EXPLAIN why you chose the answer you did!
When you have completed your pre-test… 1. Do cats eat more in the daytime or nighttime? 2. On which continents can rainforests be found? 3. What would happen to a student if he/she didn’t sleep for 48 hours? 4. Which brand of dish soap makes the most bubbles: Dawn, Ivory, or Palmolive? 5. What is the best brand of breakfast cereal? 6. Does temperature affect the life of a battery? 7. Why is eating junk food bad for your health? • Take out a sheet of notebook paper and number it from 1-7. • Read the following questions and determine if they are testable. Write “T” if you think they are testable and “NT” if you think they are not. Explain what makes the question testable or not for each number.
Testable Questions Rules for Creating Them!
A good scientist asks many questions; however, only those questions that are testable using science experiments are useful to a scientist.
Now that you can identify a testable question…let’s see how to actually WRITE a testable question! Testable questions are always about changing one thing to see what the effect is on another thing.
Sample Testable Question Does changing the height of the ramp affect the speed of a car going down the ramp?
In a scientific experiment, these two blanks have special names: variables – things that can change. Testable Question Formats • Does changing _______ affect _______? • How does changing _____ affect _____? • If I change ______, will it affect ______?
Testable Questions have two parts: • An independent variable • A dependent variable
Let’s compare the two types of variables… • Dependent Variable • What is measured in the experiment • changes because of what you changed on purpose • Independent Variable • Changed by you ON PURPOSE • There can be ONLY ONE
Testable Question Formats independent variable dependent variable independent variable dependent variable dependent variable independent variable • Does changing _______ affect _______? • How does changing _____ affect _____? • If I change ______ will it affect ______?
Example: • Does changing the height of the ramp affect the speed of the car going down the ramp? • Identify the IV and DV in this question.
Practice • Does the temperature of water affect the time it takes a sugar cube to dissolve? Identify the INDEPENDENT variable Water temperature Identify the DEPENDENT variable Dissolve time
Let’s practice writing a few… Does carbon dioxide in the atmosphere cause the atmosphere to warm? Ask yourself: 1. Which variable can I change ON PURPOSE (IV)? 2. What is going to change because of what I changed (DV)? Write the testable question: Does changing the amount of carbon dioxide affect atmospheric temperatures?
Is achievement in school higher when students are tested frequently? Ask yourself: 1. Which variable can I change ON PURPOSE (IV)? 2. What is going to change because of what I changed (DV)? Write the testable question: How does frequency of testing affect student achievement?
Do crickets chirp faster in warmer temperatures or cooler temperatures? Ask yourself: 1. Which variable can I change ON PURPOSE (IV)? 2. What is going to change because of what I changed (DV)? Write the testable question: How does the change in temperature affect the speed of a cricket’s chirp?
Since we are having a quiz on identifying variables next class, let’s practice some more!!!!
Find your missing experiment! • Every one received an orange card in class with some important experimental information on it! • Your job is to find which testable question you go with. • When all parts of the experiment have been found, write your question on the bulletin board paper and determine which variable (IV, DV, or CV) your piece of information goes under. Write the information on the paper. • When you are confident in your answers, tape your paper on the gray board (make sure not to cover up another group’s answers)! • Any questions?
Going back to our Science Starter… Jared investigated chemical reactions based on smell, color change, and release of bubbles. What types of evidence would support any conclusion Jared makes? • An observation • An estimation • A calculation • A measurement
Observations • An observation is a gathering of information using our five senses: • Taste • Smell • Touch • Sound • Sight • There are two types: • Qualitative • Quantitative
Inferences • Inferences are reasonable conclusions made from observations. • Inferences are based on your past experiences and prior knowledge. • Inferences are often changed when new observations are made.
Here are some examples! • Observation: The grass on the school’s front lawn is wet. • Inferences: • It rained. • The sprinkler was on. • There is dew on the grass from the morning. • A dog peed on the grass! • All of these inferences could possibly explain why the grass is wet and are based on prior experiences.
Tracks like these are common in parts of New England and in the southwestern United States. What do you OBSERVE? What can you INFER?
Qualitative Observations • Qualitative observations describe what is observed. • “Qualitative” = quality (descriptive) • Adjectives are used to make observation • Examples: • The flower has soft petals. • Mrs. Tindall looks sleepy today.
Quantitative Observations • Quantitative observations measure what is observed. • “Quantitative” = quantity (numbers) • Uses numbers to make observations • Examples: • The flower has seven petals. • Mrs. Tindall has two eyes.
Just a little more practice… • EVERYONE take out notebook paper • Watch the upcoming video clip and write down as many observations as you can • As a neighborhood, combine your observations in a data table • For each observation, make an inference as to what you think will happen in the movie