Magic Number Squares (and a magic trick..)
 
 
 
worksheet (one for each student)
magic trick ... six sets as a "prize" for students.
number squares ... print, laminate and cut. At least two for each student.
Prepared posters for lesson demonstration
17
10
13
12
19
3
24
15
21
20
27
16
Lesson:
1) Demonsrate, using the posters you have prepared, how "Magic Squares" work. The total along any line, horizontal, vertical or diagonal is the same. (On the poster the "magic total number" is 34).
2) The second poster has numbers missing. Show how you can work out what they are. (First show that the total is 58, and then work it out from there.)
3) Give out the number squares (2 each) and let them work out the total number. The teacher should be wandering about the class asking individual students about the total number.
4) Give out the worksheet.
5) When they have finished, show then the "magic trick! (see below). Dont tell them how it works until you have done it about six times. Then tell only to those students to whom you are giving the "magic trick". Let them try it on their friends!
Magic Trick cards
Show the six cards with the numbers to your friend. Ask him or her to pick any number greater than one that he/ she can see on one of the cards. He/ she must not tell you that number. Ask him/ her to give you all the cards that have that same number on it. You then tell the number that he/ she has picked. (Just add the top right corner number on all the cards given you, and that is the answer!)
Click on the red boxes for printable links!