## Sunday, June 26, 2011

### This is a fun riddle (be careful it's not what you expect)

What is heavier a pound of feathers, or a pound of gold?..........................................................................................................................................It's actually feathers!

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Weights of feathers are given in Avoirdupois units whereas gold is given in Troy units. A Avoirdupois pound is 453.59 grams whereas a Troy pound is 373.24 grams

## Sunday, June 19, 2011

I will be posting sporadically this summer but will start back up full-time in August. Please contact me if you have any ideas or math subjects that you want me to post about.

## Friday, June 17, 2011

If anyone is looking for some last min ideas, feel free to check out Vi Harts website http://vihart.com/ for awesome videos

## Saturday, June 11, 2011

### Working On A Detective Story To Teach Math Properties

[Door slams open and in walks a pretty, blond, number 1 with high heels]

Number 1: "You a detective"

Detective Number 4: "You askin, or are you tellin"

Number 1" What difference does it make"?

{Detective number four is staring out the window]

D4: "The difference is always in the maken tootse"

Number 1: Listen, i need help! Now, are you the detective i need to speak with or not?"

D4: "You don't need a detective love, you need muscle and muscle aint what i do ya see?"

D1: "How do you know what i need?"

[detective number 4 turns and looks her over]

D4: I know, cause them heels been talkin since you turned the corner on Elms street. Whose in trouble huh? Your husband, Your lover. What difference does it make...you need muscle and muscle ain't what i do.

[detective 4 turns and looks back out the window]

Number 1: It's my brother...x...he's got himself into some trouble and now he's got himself held up

D4: Whats this got to do with me heels?

Number 1: He needs your help detective...I, need, your, help [she gets closer to and puts hand on his arm]

D4: Let me get this straight, your baby brother shook some hands and bet on black when he should of bet on red and now that he wants to take someone elses money for a ride you volunteering my services? I think I'll pass sweetheart

D1: It's not that simple. He didn't just shake hands with anyone, he shook hands with the likes of "three eyes"

[detective number four turns and looks at her]

D4: "three eyes"?

Number 1: "yes, three-eyes and if i don't help him their not only going to hurt him, their going to hurt his wife and kids...two boys, both still fractions"

D4: "you got that right tootse, three eyes is gonna off him, his wife, his fractions and you". You want my advice, I'd grab them kids and take a one-way train out of this state"

Number 1: And tell his kids they don't have a father anymore

D4 "it's better than the alternative"

Number 1: "Listen, either your going to help me or i'm going by myself...i can take care of myself but i can't let anything happen to those little fractions"

[detective 4 starts daydreaming of those two little fractions]

D4: "Where's he held up at"

Number 1: "Downtown, in the old abandoned parenthesis...are you really going to help us? [big smile]

D4: "I didn't say i was going to help...but i'll make a few phone calls. Now you go on home and call me tomorrow, you hear?"

Inner monologue "i always was a softie when it came to blond hair and high heels"

[Shows detective standing outside of abandoned parenthesis, smoking with a top hat. A gloomy, cloudy night]

{detective peeks through the window and sees

(5x - 3)

x is the brother

3 is “three eyes

5 is a soldier

The minus symbol is a knife

[detective moves to the door of the parenthesis to knock but hears the conversation going on inside”

#3 “Listen...see...i’m tired of waiting for my money to appear. I told you you had 24 hours to get me my money and the times winding down. Tell me why i shouldn’t cut my losses if you know what i mean?”

x “Please, think of my kids, their only fractions”

#3 “It ain’t me who needs to be think of your kids x, it’s you”

x: “Please, i promise i can get it by this time next week”

#3: “You got to be kidden me, you know who i am? I’m done dealing with this guy...time for you talk to the worms”

[detective number four knows what he has to do, he breaks through the parenthesis door and “distributes punishment” to 5x and 3 like so

(4)(5x) - (4)(3)

20x - 12

Latter shows the grave of the detective, with the blond in heels over looking, holding the hands of the little fractions.

Number 1“this man combined his life to save you boys, you remember him in your thoughts ok?”

The End

﻿

## Saturday, June 4, 2011

### Parabolas and Water Fountains

The term parabola is often associated with the quadratic equation but students often encounter parabolas much earlier in their studies. For many, a parabola is simply a “u” or an “n” shape; either the top half of a circle or the bottom half. Later, when students start transforming the graphs of functions they begin to notice that parabolas can be wide or narrow in addition to being the shape of a “u” or an “n”. It was Apollonius who gave the shape its name, but it was Galileo who showed that projectiles falling under uniform gravity follow parabolic paths.
We can find parabolas everywhere in nature including water fountains.

What better way to introduce parabolas to your students than to take them to the local park and view the water fountains (If travel is an obstacle, look to your hallway to investigate the drinking fountains).

-Is the shape positive or negative?

-Is it narrow or wider than the graph of x^2

-Where is the vertex?

-Where on the graph is its slope zero?

-Where on the graph is its slope positive?

-Where on the graph is its slope negative?

Extra credit type of questions:

-What is a way to determine the area under the parabola?

-Given two parabolas and two potential equations, which equation is probably the best fit for which graph?

More involved experiment:

-Have your students use yard sticks for your x and y axis and try to find the equation of the parabola.