"I'm Thinking of a Number" Activity for Writing & Solving Equations
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Put equation solving in a new arena with this "I'm thinking of a number" format. 

Here are some possibilities to use or combine:
1.  Prepare an overhead sheet with 5 to 10 "I'm thinking of a number" problems.  Show and read the problems aloud for a class activity or quiz.
 

2.  Prepare five to ten 3x5 cards with "I'm thinking of a number" problems.  Deal out the cards to student volunteers and ask them to read aloud as the class solves the problems.
 
3.  Ask students to write their own "I'm thinking of a number" problems  (with answer) to exchange with other students, or for you to read aloud or put on the overhead.

You can ask students to solve for "just the answer", but it will be better served if you ask for an "equation and answer".
 

Sample Questions:


"I'm thinking of a number.  If you multiply my number by 5 and then add 6, you will get 51.  What is my number?"
(ans = 9)
 

"I'm thinking of a number.  If you multiply my number by 3 and then subtract 5, you will get 40.  What is my number?"
(ans = 15)

"I'm thinking of a number.  If you multiply my number by 6 and then add 13, you will get 85.  What is my number?"
(ans = 12)
 

"I'm thinking of a number.  If you divide my number by 2 and then add 10, you will get 52.  What is my number?"
(ans = 84)
 

"I'm thinking of a number.  If you divide my number by 5 and then subtract 7, you will get 5.  What is my number?"
(ans = 60)
 

"I'm thinking of a number.  If you multiply my number by 2 and then add 3 times my number, you will get 55.  What is my number?"
(ans = 11)
 

"I'm thinking of a number.  If you divide my number by 3 and then add 4 times my number, you will get 390.  What is my number?"
(ans = 90)
 

"I'm thinking of a number.  If you multiply my number by 5 and then subtract 48, you will get my  number.  What is my number?"
(ans = 12)
 
 

 Keep looking!  You'll find the number!