Archived from Englipedia.
Originally submitted by Patrick Bickford on May 01, 2008.
MATERIALS NEEDED:
- A deck of cards: Take out the 10s, jacks, queens and kings
- A scratch pad and pencil
DETAILED EXPLANATION:
- Before the trick, teach the kids trick-specific vocabulary: double and times. While this trick can be conducted in Japanese, the point of the trick is to capture the attention of numbers in English.
- Have a student shuffle the cards and fan them out. Have a student comfortable with numbers spoken in English to, "Choose a card."
- Tell them to, "Write the number on the paper," and put the card aside face-down. As the 'trick master', you should never see the front of the cards or what is written on the scratch pad.
- Then, tell them to, "Double the number. Plus 5." Finally, have them, "Times the number by 5."
- Now, tell them to "Choose another card. Plus the card to the number on paper." Lastly, tell the student to, "Say the number."
- Here's the secret to the trick: Take the number they give you and MINUS 25 and you are left with a double-digit number. The single digits of that number are the two cards the students chose.In your head, subtract 25 from the total. The two digits you get are the same as the two cards they chose.
- Unbelievable? No...just a mathematical trick that will capture your students' attention for the remainder of the class.
- Get comfortable with the card trick before you show it to the students. The last thing you want to do is mess up doing the trick...I've done it; it's not fun!
TEACHING SUGGESTIONS:
-This trick is best done on a student who is quite comfortable with numbers in English.
-This trick is best used as a introduction into numbers and should capture your students attention for the entire class, especially if you tell them you will show them the magic trick after class.