Sunday, March 21, 2010

Integer Tic-Tac-Toe (Teaching multiplication of negatives and positives)

I created a tic-tac-toe game to help kids distinguish between multiplying negatives and positives. Use the same board but use + and - instead of x and o.  Next have each player pic a square that is theirs. Have them place a + or - symbol beside the square and what ever goes inside must first be multiplied by the - or the +.

if you place a - inside a "+ charged square" the square becomes negative
if you place a - inside a "- charged square" the square becomes positive

Tuesday, March 9, 2010

Optimus PrimeNumber Alg Robot

They must solve for the unknown variables to beat the robot

Subtracting Integers With Hats

Assign each student a number from -10 -> 10

Have students make hats and color their numbers on the hats

Have all students leave their hats on their desk and go to the back of the room and form a line

Give each student a problem -9-1 = ?

They must solve the problem , go to the seat with the correct answer and place that hat on their head

New Ways to Teach Number Lines

Use Steps or a Football Field

Pythagorean Shoes

Have students take off their shoes, right shoes lined up behind right (left behinf left). Have students use C^2 = A^2 + B^2 to calculate the hypotenuse

Got a Lot of Shoes? Let's Learn Pythagoreans Theorem
What you'll need:
ruler or yard stick 
pen and paper
1st: gather up as many shoes from your closest as you can 
2nd: Since our Pythagorean Theorem only works for 90 degree triangles. line your shoes up to for the letter L (like this)

3rd: Label one line of shoes (we call legs) of your triangle A, and the other line of shoes B
4th: Measure each line of shoes with your measuring device and record them on your paper
     A =
     B =
Now we have enough information to solve the distance from the tip of one line of shoes to the tip of the other line of shoes. We call this line the hypotenuse 
5th: Using Pythagoreans Theorem A^2 + B^2 = C^2 solve for the distance of C, our hypotenuse. 
C = Square root(B^2 + C^2)
6th: Plug in your recorded information for A and B and solve for C. Hint: make sure your using the same units like inches or cm's. Record your answer below
C =  
7th: After recording your data, use your measuring device to measure the hypotenuse (the distance from the tip of one line of shoes to the tip of the other line of shoes). Did you get the same answer?
Questions To Ask Yourself
Say, instead of measuring with your ruler you counted up the size of each shoe for the distance of each line of shoes. Would your answer change? Why?
If you would have mixed multiple units of measurement like cm's and inches while working on the project, versus using the same measuring unit, how would this have effected your answer?