Remove One is one of my favorite games! It's a great way to teach probability and the students love it. I've been using it nearly every year since I was introduced to it through a program called the Mathline Middle School Math Project, sponsored by PBS (back in 1997?). I was involved in the program through my graduate studies at Allentown College of Saint Francis DeSales (now DeSales University). Anyway, this year, my student teacher is teaching our probability lessons; so she is the one who taught this lesson.
This is how the lesson works: 1. Students use a piece of paper as their "game board" and number the paper from 122 (or 212) . They then place 15 chips next to the numbers. They are told that they can place one chip next to every number and then place the extras next to any number they want. Or, they can leave some numbers with no chips and put several on others. Usually, they place the chips like those in the picture to the right. 2. Once students have their chips set up, the teacher rolls 2 dice and finds the sum of the numbers that are rolled.
3. If students have a chip next to that sum, the students may remove ONE chip from their paper (thus the name of the game Remove One).
4. Play continues, with the teacher rolling the dice and the students removing one chip each time the corresponding sum is rolled. The "winner" is the student who removes all of the chips first.
Without much class discussion, we play the game a second time. Normally, I just ask them to make some quiet observations to themselves before placing their chips again. Students typically notice that the sums of 6, 7, and 8 are rolled the most often and that 2 and 12 are usually rolled the least often, so they arrange their chips differently.
After the second game, we have a discussion about all of the possible outcomes (sums) one can get when rolling 2 dice. We also discuss how many ways there are to roll each of those outcomes, and what the probability is of rolling each sum. We find this probability in fraction form, and then often convert them to decimals and percents.
After this discussion, we play the game for a third time, and students' "game boards" often look a bit different!
This year, since I was observing rather than teaching, I was better able to hear some of the students' quiet comments to each other... "There's a better chance of getting a seven." "I'm not going to put any on 2, because it still hasn't come up."
When I started discussing this lesson with my student teacher, I searched for the lesson online, just in case it was around, and I found it right away. Click HERE to see the full lesson plan from PBS. Have you played this game? What other probability games do your students enjoy?
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3 Comments
Anne
6/10/2018 10:16:13 pm
Hi  we play a race game that is very similar. they number 112 on grid paper or make a grid 12 x 12. They place their piece on one of the numbers and then the dice is rolled, if their number comes up, they can move one square. First to the finish line wins. Can be played as a class or in small groups. Some have to figure out why 1 doesn't get rolled.
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Sarah
5/21/2019 11:12:24 pm
Thank you so much for this game. I had planned on it being an anticipatory set for the lesson, but the conversations, questions, and connections the students were making were so great, we spent the whole period on it. I recorded as many wonderings and observations as I could on the board between rounds, we reviewed the notes and drew more conclusions, then they recorded what their next strategy would be. Awesome, thanks!
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8/3/2019 02:16:17 am
I feel that this is really a good mathematical game. But too bad because I was not able to play it when I was still a student. It could have been a better way for me to understand the complicated world of mathematics; a subject that is full of complexity that had not been friendly to me ever since! Remove One is a probability game that will make you think a lot! It is quite stressful, but it is enough to make you happy that's why I will try to learn it as soon as possible.
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AuthorHi, I'm Ellie! My mission here is to support teachers as they work to provide engaging, meaningful experiences for their students. I've been in education for 25 years, teaching all subject areas at both the elementary and middle school levels, and am here to share what I've learned through those years, as well as what I continue to learn. I hope you'll find some ideas or resources here to help you out! Categories
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