Identifying Variables, Designing Investigations, & Writing Hypothesis

Reflection on Learning – Where are you & why? (4) Highly Proficient ** (3) Proficient I can complete all of the task at a 3 and identify situations in other classes and the real-world where it would be appropriate to use the scientific method I can teach the tasks at a 3 to a friend or family member and explain my thinking I can identify and explain all parts of the scientific method (observation/question, research, hypothesis, experiment, collect/analyze data, conclusion and variables) I can work through the scientific method to complete an experiment and explain my findings using details from the lab (2) Partially Proficient (1) Minimally Proficient I can identify and explain most of the steps of the scientific method I can work through the steps of the scientific method to complete an experiment but I struggle when asked to explain my findings With help from the teacher, I can identify and explain the parts of the scientific method With help from the teacher, I can work through the steps of the scientific method to complete an experiment and explain my findings

3 Kinds of Variables Independent Variable Dependent Variable Control (Controlled) Variable

INDEPENDENT VARIABLE Something that is changed by the scientist What is tested What is manipulated WHAT I CHANGED!!!

DEPENDENT VARIABLE Something that might be affected by the change in the independent variable What is observed What is measured The data collected during the investigation WHAT I MEASURED!!!

CONTROL VARIABLE A variable that is not changed Also called constants Allow for a “fair test” WHAT STAYS THE SAME!!!

For Example:

Identify the variables in this investigation. Students of different ages were given the same jigsaw puzzle to put together. They were timed to see how long it took to finish the puzzle. Identify the variables in this investigation.

What was the independent variable? Ages of the students Different ages were tested by the scientist

What was the dependent variable? The time it to put the puzzle together The time was observed and measured by the scientist

What was a controlled variable? Same puzzle All of the participants were tested with the same puzzle. It would not have been a fair test if some had an easy 30 piece puzzle and some had a harder 500 piece puzzle.

Identify the variables in this investigation. An investigation was done with an electromagnetic system made from a battery and wire wrapped around a nail. Different sizes of nails were used. The number of paper clips the electromagnet could pick up was measured. Identify the variables in this investigation.

Independent variable: Sizes of nails These were changed by the scientist

Dependent variable: Number of paper clips picked up The number of paper clips observed and counted (measured)

Controlled variables: Battery, wire, type of nail None of these items were changed

The higher the temperature of water, the faster an egg will boil.

The 3 Variables Independent variable – temperature of water Dependent variable – time to cook an egg Controlled variable – type of egg

The temperature of water was measured at different depths of a pond.

The 3 Variables Independent variable – depth of the water Dependent variable – temperature Controlled variable – thermometer

Variables Videos Independent and Dependent Variables - https://youtu.be/nqj0rJEf3Ew - 3:16 Introducing Variables - https://youtu.be/0A55QRyJHPM - 1:30 Variables with MooMoo Math https://youtu.be/-mVHzIDN0A8 – 3:20 Variables Song – to the tune of If You’re Happy and you Know it - https://youtu.be/hwU3YL_SD70 - just use up to 1:06 Crash Course Kids – Engineer Videos – watch all three in order as they lead into each other Case of What-ifs - https://youtu.be/2GaKPMlkdO4 - 3:54 Engineer Design Games – https://youtu.be/4TYLXqrdUMw - 3:20 Bowled Over - https://youtu.be/BXFU86GNmrg - 4:37 Identifying Variables using MythBusters - https://youtu.be/l0jTMDtX4WY - 6 minutes with external links to specific MythBusters clips to watch and quiz

Designing Investigations

The greater the amount of soap in a soap and water mixture, the bigger a soap bubble can be blown. Design an investigation to test this hypothesis. What exactly will be changed? How will it be changed? (IV!) What exactly will be measured? How will it be measured? (DV!) What needs to stay the same to make this a strong, accurate experiment? (CV!)

The farther a ball drops, the higher it will bounce. Design an investigation to test this hypothesis. What exactly will be changed? How will it be changed? (IV!) What exactly will be measured? How will it be measured? (DV!) What needs to stay the same to make this a strong, accurate experiment? (CV!)

Designing Investigations Videos Experimental Design in Science - https://youtu.be/7q8acfBx5to - 4:15 How to Video – Design an Experiment (using Dog Treats) - https://youtu.be/2Dv2d2OeiPY - 2:57 Experimental Design – Controlled Experiment – Using a Chipotle Taste Test example - https://youtu.be/FIu5OS-4zZk - 7:37 – a bit long, a little dry speakers, but kids might like the topic/experiment

Writing Hypothesis

Writing a Hypothesis Hypothesis – an IF…Then statement that identifies variables and gives your prediction 1st – If (Independent Variable) 2nd – Then (Dependent Variable) 3rd – Prediction 4th – Because (reason for your prediction) If….(IV)….Then….(DV)(Prediction)….Because…..

Hypothesis Examples If plants are watered with different types of liquid then plants watered with sugar water will grow taller than the other plants because it will provide more nutrients for the plant. If a diet coke and coke are placed in a container of water then the coke will sink because it is more dense.

Hypothesis Practice 1.) How does the amount of daylight affect the number of eggs laid by a chicken? What is the IV? What is the DV? Write the parts hypothesis. If (IV) Then (DV with prediction) Because… Put it all together

Hypothesis Practice 2.) How does classroom temperature affect students’ performance on a test? What is the IV? What is the DV? Write the parts hypothesis. If (IV) Then (DV with prediction) Because… Put it all together

Hypothesis Practice 3.) How will batting practice affect a player’s batting average? What is the IV? What is the DV? Write the parts hypothesis. If (IV) Then (DV with prediction) Because… Put it all together

Hypothesis Practice 4.) How does advertising affect the sales of Snickers? What is the IV? What is the DV? Write the parts hypothesis. If (IV) Then (DV with prediction) Because… Put it all together

Hypothesis Practice 5.) Does adding fertilizer affect the growth of a plant? What is the IV? What is the DV? Write the parts hypothesis. If (IV) Then (DV with prediction) Because… Put it all together

Writing Hypothesis Videos How to form a hypothesis - https://youtu.be/bp2fbzWZDmA - 4:06 How to write an if, then, because hypothesis statement - https://youtu.be/HtMkHBg-xTA - 3:03 Lollipop Licks Activity - https://www.sciencefriday.com/educational- resources/how-many-licks-controlling-lollipop-licker-variation/ You could get tootsie lollipops and assign this as homework! There is even a difference worksheet you can assign to follow up after they all get such different answers - http://www.sciencefriday.com/wp- content/uploads/2015/08/Lollipop-licker-differences-table.pdf You could have the kids fill out this form online after they do the experiment https://docs.google.com/forms/d/e/1FAIpQLSezV3- vEGHFe_hGiUI19LM8IcP54EfqBUk0IKOigWdAm-Qptw/viewform You could watch this movie before, or after Lollipop Hypothesis - https://www.sciencefriday.com/videos/the-lollipop-hypothesis-2/ - 4:47