Effect: 

The magician has three rows of cards. An audience volunteer picks a card in his/her head and tells the magician what row it's in. The magician does that three times and on the third time tells the volunteer what their card was. 

Supplies: 

21 cards

Secret: 

First lay out the cards face up, 3 across and 7 down. 

Have someone think of a card and tell you what row its in. 

Pick up the 3 rows, row by row (down), making sure to pick up the row that the card is in 2nd.  

EXAMPLE:  Let's assume the volunteer secretly chose PINK-6 and then told us their card was in the second row.  We would pick up the rows and we would make sure the pink row was picked up second so that it was in the middle of the deck. 

Put down one card per row. 

• Ex: First do this *** (let's pretend the stars are cards).
• Then this: *** and so on (7 times). 

In our example, we'd put down BLUE-1, BLUE-2, BLUE-3 then go down to the next row and place BLUE-4, BLUE-5, BLUE-6 and so on.

Then ask the volunteer where the card is in now. 

Pick up the rows again, like before -- still making sure that you pick up the row that the card is in 2nd.

In our example, the volunteer would say their card was in the first row.  You would make sure that row was in the middle of the deck

Then ask the volunteer which row the card is in now. 
(You can get dramatic and tell them to think really hard about it... pretend to be reading their mind)

Then count four cards down in that row. 
(It appears more magical if you count to yourself... people won't realize you're counting four cards down).

The fourth card is their card!!

In our example, the volunteer would have said their card was in the last row.  Four cards down is PINK-6!

You could also pick up the 3 rows as before, again, making sure to pick up the row that the card is in 2nd. And then the 11th card would be the card you were searching for. You could show this card by throwing all the cards face down one by one on a pile while remembering which one is the 11th, and then take the card out of the pile... That way it would seem even more magical.