Modeling Your World Activities

These are a suggested list of activities for Modeling Your World. You need not do them in this order, and you may not have time for all the activities. In other words, these are ideas for you to pick and choose from if you want them.

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• Interviewing. Students interview in pairs. Then, each student introduces his or her partner, by either going around the room or by making the next student introduced have something in common with the person who was just introduced. For example: Sarah introduces Nicole: Nicole is 13, goes to DSA and likes pizza, the color blue, and reading science fiction. The next person introduced must have at least one thing in common -- Ryan is 13, Mike likes pizza, and Michelle goes to DSA, so any one of them could be introduced next.
• Students line up in order of birthdays, but they can't talk while they arrange themselves. Set a time in which they have to line up. Students pair off in this line. (instead of birthdays, can use alphabetical order, but don't use last names if there are siblings!)
• Go around the room, making each person say his or her name with a descriptor starting with the same letter (like "Curious Chris"). Each person must say his name and adjective as well as all the names and adjectives previous.

What is Modeling?
Setup: a rock and a model car
Explain what modeling is, and that it is trying to understand something by looking at something else. The thing you study behaves like the thing you are modeling only partially, given certain rules, or parameters. Hold up the rock and ask what it could be a model for. Tell the students it is your model car. Drop the rock. Ask the students how the rock can be a model car. Answer: it is a model of a car with no wheels and no engine. So it is a model of a car, but a car in very specific circumstances. This is the way all models work; they all make assumptions to make the model easier, and they will work only if you know what the model's restrictions are. The rock makes a good model of a car falling off a cliff, but not of a car driving down the highway. Conversely, hold up the model car. It is your model rock, because it falls just like a rock.

Rope Tricks Modeling
Setup: Ropes for each student, as well as a teacher or helper who knows the rope tricks

• Ropes modeling chemistry: chemical bonds; Single bonds are longer and weaker than double bonds (rope folded in half to form a double bond), which are in turn longer and weaker than triple bonds (rope in thirds)
  
• Ropes modeling physics: dropping it (gravity) or tension
  
• Ropes modeling biology: snake movement
  
• Ropes modeling math: A/D + B/D + C/D = (A+B+C)/D
  Division is modeled by forming a knot (A over D and store the result makes a simple knot). So you can either make each knot separately (left side of equation), or all at once (right side). The all at once method is the rope trick. You gather all the loops first, then tie. Have the students do the left side, and you do the simplified form to see if the simplified form is indeed quicker. You can then teach the students how to do the quicker method.
  You can also model math by tying a bow, simplifying to (1/2A)/(1/2B).

Rabbits and Wolves
setup:none
Use the Rabbits and Wolves model, going through the parameters and what they all mean. Then let the students play with the model, trying to find a set of parameters that keeps a stable environment, ie. the wolves survive. If someone finds one, talk about what parameters they chose, and they run it again on the projected computer. Even with the same parameters, you may not get the same results, due to the random nature of the movement of the animals in the model. Talk about randomness and probability.

Fire Applet
Setup: none
Explain how the Fire Applet works. Show how none of the fire burns at probability zero, and all burns at probability 1. Make sure all the students understand probability and putting that probability in decimal or fraction. Then have each computer group run 10 runs (or 6 or 8 if you don't have much time) at various probabilities.
You can then use the Stem and Leaf Plot to discuss the range of various probabilities and what results they actually get. Groups around 50% should get a wide range, while people closer to 0 or 100% get relatively consistent burns. Or, you can use the Simple Plot to see that the amount that burns is not linear compared to the burn probability, but instead an S-curve. Discuss what this means (basically that, around 50%, you get a much steeper curve, meaning that a lot less change in conditions can drastically change the amount that actually burns) These results can help explain the Stem and Leaf Plot results, and vice versa, if you have time to do both.

Air Foils
Setup: airfoil materials for all students: paper, cans with rocks, pins, strams, and clothespins
Talk about what makes an airplane fly, using terms such as lift, drag, high and low air pressure. Ask the students what they think an airplane wing should look like. You can use FoilSim either before or after the hands-on activity to further demonstrate the physical concepts. Let each student make an airfoil and test it in the wind tunnel, seeing how angle affects lift. The airfoils should be set up in the following way: Airfoil created out of cardstock paper, with a straw through the side. This straw has the airfoil on one end, and is attached to a clothespin at the other. They are connected by a pin piercing through one of the clothespin's pieces of wood, then the straw, and then the other piece of clothespin wood. The clothespin is then clipped to the soda can top. The apparatus should have the soda can as a weigthed base, and the pin as a pivot for the straw and airfoil as the foil lifts in the airtunnel. Explain what an airtunnel is and how it works before testing the airfoils.

Implosions and Air pressure
Setup: small, portable burner outside, a bowl of ice water, an empty soda can, and tongs to hold the soda can

Star Logo
Setup: Make sure all the computers have a working version of StarLogo on them. Topics to include:

• How the program works, turtles v. observer commands
  
• Moving turtles in patterns, repeated commands and procedures
  
• Rabbits and Grass model, or
  
• Termites and Wood model

STELLA
Setup: Make sure all the computers have a working version of STELLA on them.
Explain what STELLA is (modeling program), what it does (time based problems/ calculus), and how it is useful (recognizing mathematical relations through pictures and patterns, doing calculus without doing the math). Making a simple model with the class, guide them through Stocks (like Nouns), Flows (like Verbs), Converters (like adjectives or adverbs), and Connectors (tell computer which converters are describing which things, like putting the words in order in a sentence). Also show the students how to use the dynamite. Once the model is complete, show them how to make a graph, table, and numeric display. Make sure they understand what everything in the RUN SPECS menu means. Models you can make include basic population or flu model.
You can then have the students make a more complicated model with you only giving them the information they need and helping students with the harder parts, like graphing converters. This can be the flu model or lynx and hares. Depending on their skill level, you may want to show them the other levels of STELLA (interface and math), and how to use sliders. Or they can improve the model they just made (immigration, other disease, vaccination, etc).

Stella Models to download:

• Simple population
• Extended population model
• Flu Model
• Lynx and Hares

Galaxsee
Setup: Make sure all the computers have a working version of Galaxsee on them.
Lesson plans at GalaxSee Lesson Plans . Appropriate lessons include Earth's Orbit and Rotation and Flattening.

Daredevil Cars

Mini-projects
If there is time at the end of the week, let pairs of students try to answer questions posed by the teacher, or let them come up with their own questions. Have them figure out the best way to solve the problem, and then answer it, and present the answer to the class. Depending on time, you may want each group to use an existing model, or modify a model they made earlier in the class. Some sample questions:

• Using information about the distance from the earth to Mars, figure out the length of a Martian year (modifying Earth/Sun Galaxsee model)
  
• How does vaccination curb an epidemic (adding to flu model, possibly using sensi specs)
  
• How does a speed trap affect traffic outside of the actual zone of the speed trap? (using existing StarLogo model)