{"product_id":"addition-within-100-csi-mystery","title":"Addition Within 100 CSI Mystery Worksheets | Grades 2–6 | Back to School","description":"\u003cp\u003eSeptember CSI math worksheets for 2nd grade and 3rd grade on multiples of 3 and 5, even numbers and a hundreds chart, run as a CSI Mystery Detective case called The Suspect Number. It holds up just as well as 4th grade math review. Everything prints ready to use in color or black and white, with answer keys for every page. The only fact at the start is that the mystery number is under 100, so students run a real investigation - evidence, forensics, line-up, interrogation - shading multiples, sorting out the even numbers and cross-matching witness numbers until two suspects are left and one final puzzle decides it.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eThe Case: The Suspect Number\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eThe only thing known at the start is that the number is under 100. That leaves rather a lot of them. Your students work it the way an investigation actually runs: evidence, then forensics, then a line-up, then interrogation, with the suspect list getting shorter at every stage until two numbers are left arguing about which of them did it.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat's Inside\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eA letter-and-number cipher that decodes the opening message\u003c\/li\u003e\n  \u003cli\u003eShading the multiples of 3 and 5 on a hundreds chart\u003c\/li\u003e\n  \u003cli\u003eWorking out which of the remaining suspects are even numbers\u003c\/li\u003e\n  \u003cli\u003eCross-matching the witness numbers against the evidence so far\u003c\/li\u003e\n  \u003cli\u003eA final puzzle that separates the last two suspects\u003c\/li\u003e\n  \u003cli\u003eFull color and black-and-white versions of every page\u003c\/li\u003e\n  \u003cli\u003eAnswer keys for the whole case\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhat Is a CSI Mystery Detective Case?\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eA CSI Mystery Detective case turns a page of math into evidence. Students solve, and each correct answer removes one candidate until a single one is left. There is nothing to unlock, download or prepare - it is a math escape room made of paper. Detective activities also police themselves, which ordinary math worksheets never do: an error leaves two possibilities alive, so the class rechecks. A math activity that carries a lesson, a center rotation, or a sub plan.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhen to Use This Resource\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eIntroducing or consolidating multiples and even numbers\u003c\/li\u003e\n  \u003cli\u003eHundreds chart work that is not coloring for its own sake\u003c\/li\u003e\n  \u003cli\u003eMath centers, early finishers and independent work\u003c\/li\u003e\n  \u003cli\u003eEmergency sub plans that run themselves\u003c\/li\u003e\n  \u003cli\u003eBack-to-school weeks and end of year review\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003e\u003cstrong\u003eGrade Levels\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eBuilt for 2nd grade, 3rd grade and 4th grade. Second graders usually want the hundreds chart explained once before starting; third and fourth graders run the whole investigation independently. It also gives 5th grade students who are shaky on multiples a way to rebuild without going back to a plain worksheet.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eWhy Teachers Love CSI Mystery Detective Cases\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cul\u003e\n  \u003cli\u003eZero prep - print and hand out\u003c\/li\u003e\n  \u003cli\u003eSelf-checking by design, because an early error shows up later\u003c\/li\u003e\n  \u003cli\u003eNumber work students will actually finish\u003c\/li\u003e\n  \u003cli\u003eWorks as a whole lesson, a center, or a filler for an awkward afternoon\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eLove this resource?\u003c\/p\u003e\n\n\u003cp\u003eFollow Kiwiland Education for new detective cases, seasonal math activities and updates on discounts and new releases.\u003c\/p\u003e\n\n\u003cp\u003e\u003ca href=\"https:\/\/www.teacherspayteachers.com\/Sellers-Im-Following\/Add\/Kiwiland\"\u003ehttps:\/\/www.teacherspayteachers.com\/Sellers-Im-Following\/Add\/Kiwiland\u003c\/a\u003e\u003c\/p\u003e","brand":"Kiwiland Education","offers":[{"title":"Default Title","offer_id":62593151828338,"sku":"3496924","price":4.0,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0909\/2848\/0626\/files\/addition-within-100-math-worksheets-back-to-school-cover.jpg?v=1792612948","url":"https:\/\/kiwilandeducation.com\/products\/addition-within-100-csi-mystery","provider":"Kiwiland Education","version":"1.0","type":"link"}