Tennessee SPI Objective: Design a simple experimental procedure with an identified control and appropriate variables. Notes Science Check for Understanding Design and conduct a simple experiment that includes an independent variable, a dependent variable, and controls. Essential Question(s) 1) What are the steps of the scientific method? 2) What are experiments, and how do I design them to include independent/dependent variables, and controls? 3) How is a dependent variable different from an independent variable? SPI 0807.Inq.1 (Variables and Controls) Instructions for Students 1) Make sure you view this presentation in slideshow mode. 2) You can find instructions about how to do this by doing a Google search or by searching YouTube. 3) After you have it in slideshow mode, press the right-arrow keyboard button to advance through the presentation. 4) If you need help, please communicate with your teacher.

What is a Dependent Variable?  Often called the "responding variable" because it is the response to the factor that was previously introduced.  These are the results that you observe after you introduce the independent variable.  In other words, first you introduce the independent variable, and then you observe the response which is called the… Also called "Responding Variable"

The dependent variable should be on the y-axis Graphing Dependent Variables y-axis x-axis Link (2 min 19 sec): Video-Graphing Ind and Dep VariableVideo-Graphing Ind and Dep Variable

Example: A scientist is conducting an experiment to test how sunlight affects plant growth.  She places one corn plant 1 meter away from a sunlamp.  She places one corn plant 2 meters away from a sunlamp.  She places one corn plant 3 meters away from a sunlamp. Corn plant 01Corn plant 02Corn plant 03 What is a dependent variable in this example? HINT: What is the response to the distance from the sunlamp? The independent variable is the distance from the sunlamp A dependent variable is the plant growth

Example: A student conducts an experiment with ten 8th grade students. He uses 3 similar types of sour candy in a series of four trials. (Sour Patch Kids, Sour Skittles, and Warheads) He gives 1 piece of candy to each student and records their facial expressions to estimate how sour each candy is. What is a dependent variable in this example? HINT: What is the response to the different types of candy? The independent variable is the type of sour candy A dependent variable is their reaction (facial expressions)

Example: A student conducts an experiment to determine which type of glue works best for attaching two pieces of regular writing paper together. She places 2g of glue on each sheet of paper, and then uses a spring scale to measure how much force it takes to pull the sheets apart. Liquid-washable Glue Stick-washable Glue Stick-nonwashable She uses 3 types of Elmer’s glue in a series of experiments. What is a dependent variable in this example? HINT: What is the result from using the different types of glues? The independent variable is the type of glue Dependent variable-how much force to pull apart the paper

Example: A student conducts an experiment to determine which ink color in ballpoint pens will last the longest before running out. She uses 3 ink colors in 3 identical ballpoint pens in a series of trials. (1) Black ink pen, (2) Blue ink pen, (3) Red ink pen) She copies text from her science book. She copies the same text over and over. She writes at the same speed. The room temperature remains the same. She writes on the same kind of paper each time. (These are all constants.) What is a dependent variable in this example? HINT: What is a result from using the different color inks? The independent variable is the color of the ink A dependent variable is how long the ink lasts.

Questions Science SPI 0807.Inq.1B Dependent Variables

Questions Science SPI 0807.Inq.1B Dependent Variables

Questions Science SPI 0807.Inq.1B Dependent Variables

Questions Science SPI 0807.Inq.1B Dependent Variables

Questions Science SPI 0807.Inq.1B Dependent Variables