Number CSI - Solve the "Crime"

33 Ratings
54575 Downloads 132771 Views Updated: Tuesday, December 17, 2019 - 3:43pm
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In this middle school math activity, students must analyze five pieces of evidence to eliminate nine of ten suspects. Ideal as an end of topic activity; students need to perform operations with fractions; ratios and decimals and also interpret their results in a different context.

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July 2017
Thank you so much!
May 2017
The kids loved it! Does anyone know who suspect 1 and 3 are? They're the only two I don't recognize...
January 2017
Thank you for sharing. My sixth graders really invested time to solve these problems. I used this as the evaluation for our unit.
December 2016
I have used this activity three years in a row. Very engaging. For those asking for an answer key, solve the problems before starting the lesson and use that as your answer key.
November 2016
Awesome lesson, quick question, are the decimals on the Evidence 5 part supposed to be colons? Or are students supposed to actually be calculating decimals of the hour. Thanks!
September 2016
This is an amazing activity and I cant wait to try it with my students!
August 2016
Thank you, my kids are going to gobble this up!
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July 2016
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January 2016
July 2016
Great resource. can't wait to try it out , good job!
April 2016
nice 10/10 GG
April 2016
June 2015
Great creativity, my students will be engaged. I am confused on investigation page #2, why would you eliminate the suspects with the most money, wouldn't it be the least money? It would be nice to have an answer sheet. Thanks!
April 2017
You would eliminate the suspects with the MOST money because they are least financially motivated to have committed the crime since they have no need for more money. Therefore, suspects with the LEAST money would actually be more financially motivated to commit the crime since they had such a large need for money.
May 2015
Omg! I want to play! I will definitely be adapting this for my high schoolers; thank you!! So fun!
April 2015
Great resource. Some constructive feedback is always good. (See below). For anyone to 1-star this is a disgrace - fantastic resource for higher level year 6s. As for Evidence 2, a well taught lesson on percentages is all you need! Brilliant idea.
March 2015
I generally liked this lesson as a math enrichment activity for 6th graders. However, the Evidence 2 worksheet (requiring knowledge of percentages) was too hard for 6th graders, and required your getting all the answers right in order to eliminate two (unlike the other worksheets). I decided early on that I should eliminate Evidence 2 altogether -- especially because students could get the right answer (Suspect 3) without doing it. If I did this activity again, I would probably remove the current Evidence 2 and invent my own. BTW, you should model that on the results page, an X indicates that the person is NOT guilty. It's better to impose this rule than see students haphazardly come up with a way to mark it (and getting confused by doing it inconsistently). If I did this lesson over again, I would probably make my own Evidence 2 sheet covering a different subject area and not requiring them to order the incomes before reaching a conclusion.
March 2015
This looks fantastic! I am planning to use it as a project grade at the end of my ratios and percents unit. Thank you so much. Intensive Math Teacher 6-8
October 2014
My students absolutely loved this.
October 2014
Great resource. It fit in nicely with my alternate reality spy game.
September 2014
Could an answer key be added to downlaod?
June 2017
Do you have the answer key for evidence 4?
July 2014
Great Resource
May 2014
This was a great excercise for my middle school students. They actually look forward to solving the crime. I really appreciate all your hard work.
May 2014
Thanks for taking the time to do these lessons they are great!
February 2014
Our math was starting to get stale, and we needed something to spice it up. This lesson/activity fit the bill 100%. My colleague next door and I had our students work together in pairs to complete the task. After 45 minutes of some of the best teamwork we have seen so far this year, we went over the results. The students had a BLAST! THANK YOU, THANK YOU, THANK YOU!
January 2014
I had a different answer than the ppt indicated from evidence #2. I believe the instructions should say who has the least money, which wouldn't make sense to eliminate them.
December 2013
Hands down, best math lesson I have EVER done. Thank you from the bottom of my heart :)
December 2013
I haven't finished the activity, but are you supposed to be able to eliminate any suspects with the first piece of evidence? All of them have enough of each material to make the poison. [They may have more than enough of each material, but the ratio is still possible with any of those amounts.] If you intended for them to have exactly the ratio listed, that doesn't make much sense. You don't decide not to make cookies because you have an extra egg.
November 2013
I changed some of the material for my seniors and they loved it. It is difficult to find review material that seniors actually enjoy doing. Thanks!
November 2013
Students loved it. They were engaged throughout the project.
October 2013
What an excellent lesson! I can't wait to use it with my students. I know they will love it.
October 2013
This is great! Love it for a review exercise and makes it far more fun for the kids! Thanks!
September 2013
Is there an answer key for this?
September 2013
Some activities don't make sense. Suspects do not need to possess poison ingredients in required ratio to have the capability to make poison. Why are quantities for the marked bills' residue being subtracted?
July 2013
This was a whole lot of fun! I used it during the last month of 5th grade and they were so engaged. Thanks!
June 2013
Can't wait to try this with my students. I am sure it will be challenge to them, using math in a real-world concept.
June 2013
My students also loved this. We just completed a week of end of grade test and the kids are shutting down. Your CSI activity was a great way to continue lessons and a way for the kids to enjoy leanring. Thank you for the lesson!
May 2013
My 7th grade students absolutely loved this activity. It was very challenging for them and completely aligned to my standards. Great for an end-of-year project when they're restless and have already turned in their textbooks for the year.
April 2013
Very easy to differentiate. Engaging. Students were challenged and had fun with this. Some wanted to create a similar activity.
April 2013
This is a great way to assess in several different areas. Thanks!
March 2013
I really appreciate that this resource could be used successfully as an assessment with a variety of my students. I also see ways that I could adapt it to make it more open ended. Love that it asks kids to justify their answer.
January 2013
Looking forward to trying this in my classroom!! Thanks!
November 2012
Fantabulous!!!! Thank you :):)
October 2012
Loved it!!
October 2012
September 2012
This is a great activity for later in the year. Thanks.
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May 2012
Absolutely Brilliant! Thank you
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January 2012
This is an excellent resource based on the topic of number. Pupils have to solve the crime by working out the answer to a set of questions. As they work out the answer, they eliminate potential suspects. This is a fun and engaging way to teach/assess a topic and also gives the pupils a chance to work together and to compete against each other. Thanks for sharing!