Scientific Method Worksheet
Read the following descriptions of experiments and answer the questions about them. You do not need to actually perform any of these experiments, just answer questions about their design. Experiment You want to determine which disinfecting spray kills off more germs, Clorox or Lysol. You spray two counters with juice from raw chicken. Then you spray one counter with Clorox and one with Lysol. After the solutions dry, you wipe a cotton ball on the Clorox counter and then wipe it onto a petri dish. You do the same with the Lysol counter and wipe it onto a separate petri dish. You let the plates grow bacteria for several days, then count which plate has more colonies of bacteria. Questions Name the Independent and Dependent Variables from the experiment above. Name two good Control Variables you would keep track of in this experiment. This experiment needs a Positive Control Experiment. (This means at least one more counter and petri dish.) Describe what you would do to confirm that you can measure your experiment is working as expected. Create a hypothesis for this experiment. Remember that a good hypothesis doesn’t have to be right, it just has to follow the rules. (Which spray will kill off bacteria best?) Tutoring and Test Taking Experiment
You want to see how much additional tutoring helps Biology students. You choose 10 students at random from a Biology class and assign them 2 hours of extra tutoring each week. You then give all students a test and determine the average scores for the tutoring and non-tutoring groups. Questions Name the Independent and Dependent Variables from the experiment above. Name two good Control Variables you would keep track of in this experiment. This experiment already has a Negative Control Experiment built into it. What was the Negative Control Experiment? Create a hypothesis for this experiment. Best Fertilizer for Corn Experiment You want to determine which fertilizer makes corn plants grow the tallest, Miracle Grow, Scotts, or Pennington. You plant rows of corn and treat each row with a different type of fertilizer. You measure the average height for each row after 10 weeks. Questions Name the Independent and Dependent Variables from the experiment above. Name two good Control Variables you would keep track of in this experiment.
This experiment needs a Control Experiment added to it. Is it a Positive Control or Negative Control that you need to add? Describe what you would do. Create a hypothesis for this experiment. Design Experiment – Best Laundry Detergent Describe your experiment with laundry detergent in the space below. Name the Independent and Dependent Variables from the experiment above. Name two good Control Variables you would keep track of in this experiment. Does your experiment have Negative or Positive Control Experiments? If so, what are they? If not, why don’t you need them? Favorite Soft Drink
Create a hypothesis for this experiment. Design Experiment – Favorite Soft Drink Describe your experiment about soft drink preference in the space below. Name the Independent and Dependent Variables from the experiment above. Name two good Control Variables you would keep track of in this experiment. Does your experiment have Negative or Positive Control Experiments? If so, what are they? If not, why don’t you need them? Create a hypothesis for this experiment. TURN IN WORKSHEET Your instructor will tell you how to turn in your completed worksheet and what grade it will contribute to. It is important to study your results for quizzes and exams.
