1. Each week we will post new Brain Teasers at each of three grade ranges: 3-4, 5-6, and 7-8. Select one or all three and see if you can get the right answer. Check back next week when we post the solutions, along with three new puzzles.

2. The Brain Teasers are meant to build problem-solving skills, so they may take a little while to solve. If you get stuck check the hints we provide for each question.

3. Our hints often suggest problem-solving strategies. You may find other problem-solving strategies to be helpful, too. The strategies include: make a table, act it out, guess and check, look for a pattern, work backward, make a list, work on a simpler problem, draw a picture, and write an equation.

4. In solving the Brain Teasers it helps to have a working procedure. You might want to consider this four-step procedure: Understand, Plan, Try It, and Look Back.
   Understand — Before you can solve a problem you must first understand it. Read and re-read the problem carefully to find all the clues and determine what the question is asking you to find.

   Plan — Once you understand the question and the clues, it's time to use your previous experience with similar problems to look for strategies and tools to answer the question.

   Try It — After deciding on a plan, you should try it and see what answer you come up with.

   Look Back — Once you've tried it and found an answer, go back to the problem and see if you've really answered the question. Sometimes it's easy to overlook something — that's why we call them Brain Teasers. If you missed something check your plan and try the problem again.

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