25 July 2012 - Card Trick

This is a math-based trick, so you may not be able to play it on anyone who is younger than 8 or so, depending on how good they (and you!) are at math.

Take a deck of cards and take out all the 10s, Jacks, Queens and Kings (there are 4 of each).  You also should make sure you don't have any Jokers in the deck.

Ask for a volunteer and tell them they are going to pick 2 cards and you will tell them what they are.  Tell your volunteer to pick one card and look at it.  In their head (or you could give them paper) tell them to do the following steps:

1.   double your number

2.   add 5 to your new number

3.  multiply your most recent number by 5

Finally, they need to pick another card and add that number to whatever they had last.

Have them tell you their final number.

In your head, subtract 25 from their total.  The 2 digits of whatever you have left are the 2 cards they had.

EXAMPLE: (volunteer picks an 8)

1.  double your number = 16

2.  add 5 to that number = 21

3.  multiply by 5 = 105

Pick a second card (we'll say it's a 3)  Add that to your last total 105 +3 = 108

They will tell you their number is 108

 In your head, you figure that 108-25 = 83.  So their 2 cards were an 8 and a 3!!

EXAMPLE 2: (volunteer picks a 2)

1.  double your number = 4

2.  add 5 = 9

3.  multiply by 5 = 45

4.  second card (we'll say it's a 9).  Add to last total 45 + 9 = 54

They will tell you their number is 54

In your head, subtract 54-25 = 29.  So their 2 cards were 2 and 9!!

 Try it by yourself a few times first, so you get the hang of the steps and the math.  Then try it on someone else and see it in action.  Tell us in the comments section if you tried it and if it works.

Let's pretend I was your volunteer!  My total is 69.  What were my 2 cards?

I volunteered again!  My total is 41  What were my two cards?

Post your answers as a comment and I will let you know if you were right.

24 July 2012 - Fortune Tellers

You may have made these before, maybe you call them "Cootie Catchers."  But since they don't actually seem to catch anything, I call them Fortune Tellers.  First you need to fold one, then you will label it with fortunes.

Step 1:  Start with a blank sheet of paper (lined school paper is okay, but blank paper is better).  If you have square paper, you can skip to step 2.  If you have regular paper, you need to make it square.  To do that, you fold up one corner so that it goes across the paper and meets the far edge.  It will look like this:

Bottom corner folded up, cut off the top flap.

Cut off the top flap.  Now unfold the paper and you have a square.

Step 2:  Fold the bottom left corner up until it touches the top right corner.  Make a good fold line.  Then open it up and fold the opposite way.  Open it up and you should have lines making an x across the square.

Step 3:  Fold all 4 corners in to the middle.  DO NOT unfold!

Folding in the first corner

All corners are folded

Step 4:  Turn the whole thing over so the corners are on the bottom.  Fold the 4 corners in again to make the whole thing even smaller.

Upside down, you see the fold lines but no flaps.

Corners folded over the bottom.

Step 5:  Labeling the Fortune Teller.  There are lots of different ways to do this, but the only way we can play together is if we all label the numbers and colors the same way.  So, on the side you are looking at, there are 4 big triangle flaps, and each of them has 2 sections.  Start on any flap and number the two sections 1 and 2.  Go to the next flap and also do 1 and 2.  On the other 2 flaps, number the sections 3 and 4.  It should look like this:

Step 6:  Turn it over to label the colors.  You should have 4 square flaps on the back side.  On each one, write the name of a color.  So we can play together, for this one you should use RED, BLUE, GREEN, and PURPLE (or YELLOW).

Step 7:  Turn it back over so you can write the fortunes on it.  Lift any of the triangle flaps, and you will write the fortune on the back side of the numbers.  You can write big, so there will be one fortune for both of the numbers on the flap, or you can write smaller and put a different fortune under each number.  Your fortunes should be predictions for the players future (only nice fortunes!), like "You will be rich" or "You will have 8 children"  or "You will be a doctor."

Example of a BIG fortune that covers 2 numbers.

This shows the small fortunes, so that each number has its own fortune.

To use the Fortune teller, fold the numbers back down so you see them and not the fortunes.  Fold the Fortune teller in half between the 1 and 2, where there is not already a fold.  Unfold and then do it again the other way.  Holding the numbers side up, reach under the flaps that have the colors on them and "puff" them out so your fingers go inside.  Use your thumb and first finger on both hands.  Put your thumbs toward each other and the pointers together and pull the pointers up from the thumbs to show 4 of your numbers.  Then switch and put the left thumb and pointer together, and the right ones together and pull to the sides.  Go back and forth a few times to break it in.

To play with someone, close all your fingers in the middle so they only see the colors and tell them to pick a color.  When the choose, open the Fortune teller and spell the name of the color, changing the opening each time: R (thumbs together, pointers together, E (right hand together, left hand together), D (go back to the first position).  On the last letter, ask them to pick one of the numbers they see.  Then count it out by changing positions just like before.  When you stop, have them pick one of the numbers they see.  This time, you will remove your hand and read them the fortune that is under their number.  Fold it back up and you can try again!

Variations:  You can write the names of different colors, vary your numbers, write extra small fortunes so your players will pick a number and say "top" or "bottom" and you will have 2 fortunes written under each number.

DO NOT USE A VARIATION TO PLAY HERE!

There are 2 ways to play.  First, you post a comment saying a color, number and number.  Second, you read other peoples colors and numbers, play them on your fortune teller, and post a reply telling them what their fortune was.  Other people will tell you what you go on their fortune tellers too!  The first post will be me, so play my color, number, and number on your fortune teller and tell me what I got!

23 July 2012 - Codebreakers!

In the future, we will do harder codes, but for today it will be an easy substitution code.  A substitution code means a code where you substitute a different letter for the letter you want.  The top line below is the letter you want, the bottom line is what you will write instead of the real letter.  For our code today, we will do this:

Real letter:  A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Code letter: B C D E F G H I J K L M N O P Q R S T U V W X Y Z A(use these to write in code)

For example, if you wanted to write the word "dog" in code, you would first look for the D on the top line.  Below it is an E, so that is the code letter for D.  "DOG" in this code would be spelled "EPH."

Try to write these in code:  CAT, SMART, BLUE  (answers are at the bottom of this post)

To decode a message that is already in code, you need to look for the letter in the bottom row, and see what letter is above it.  If a coded message said "EVDL"  you would look for the E in the bottom row and there is a D above it, so D is the first letter of the real word.  Solving for the other letters, you would realize that the coded word is telling you to "DUCK."

Try to decode these words:  SFE, MVDLZ, TDIPPM  (answers are at the bottom of the post)

In the comments, answer the following question:
Xibu jt zpvs gbwpsjuf gppe?

Answers for CAT, SMART, FAST
CAT = DBU
SMART = TNBSU
BLUE = CMVF

Answers for SFE, MVDLZ, TDIPPM
SFE = RED
MVDLZ = LUCKY
TDIPPM = SCHOOL