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Feel free to send in puzzles that I can add to this page. Just go to the contact page, and send the puzzle along with a solution.

Because they’re fun… at least they should be. If you’re creating a healthy, productive, exciting problem-solving classroom, then you should be doing everything you can to create an environment in which students look forward to facing challenges. Helping you do this is what this site is about. Making puzzles available to students who want them is just one small part of reaching this goal. Check out this article on puzzles.

The seats in a lecture hall are ordered 1-100. The students waiting to get in are also numbered 1-100, and they are allowed to enter the lecture hall one-by-one in order. They pick a seat according to the following rule. If the seat that matches their number is available, they sit in that seat. I...

After your rise to fame as—well, whatever you're famous for—you've decided to hire a team of bodyguards. They have agreed to payment in the form of a rectangular prism gold bar that you possess. Your agreement states that you will pay them 1/7 of the gold bar every week for 7 weeks.
Obviously, yo...

This problem is based on the game show Let's Make a Deal, which was hosted by Monty Hall. WARNING: Solving this problem may lead to good classroom arguments.
Contestants of the show were asked to choose one of three big doors, behind which were prizes.
Let's say that behind one door is a brand ne...

Let's say that when a child is born, the probability of it being a girl is 0.5.
Out of all the two-child families in the world, I have randomly selected one family that has a golden retriever named Waldo. One of the two children is a girl. What is the probability that the other one is a girl?

This problem has been circulating around the internet as an example of a problem posed at job interviews.
You have a row of 100 doors that are all closed. You are going to pass along the row from 1 to 100 switching the status of the doors. If a door is open, you closed it, if it is closed, you op...

The Jackson family raises dogs that like looking for patterns in math. In a recent litter, Lightning, one of the girl dogs , noticed that she had two more sisters than brothers. Puffles, one of the boy dogs, was disappointed because he had three times as many sisters as brothers. How many puppies...