{"product_id":"addition-subtraction-csi-math-mystery-worksheets-grades-2-5-the-valentines-surprise-card","title":"Addition \u0026 Subtraction CSI Math Mystery Worksheets | Grades 2–5 | The Valentine's Surprise Card","description":"\u003cp\u003eA mystery Valentine's card has turned up inside a student's desk, and nobody will admit who left it. That's where your class comes in. This printable \u003cstrong\u003eValentine's Day Addition \u0026amp; Subtraction CSI Math Mystery\u003c\/strong\u003e is built for \u003cstrong\u003eGrades 2–5 classroom teachers, homeschool parents, and tutors\u003c\/strong\u003e who want focused math practice wrapped in a story students actually care about solving.\u003c\/p\u003e\n\u003cp\u003eStudents work through a series of clue pages, use their answers to eliminate suspects, and race to crack the case — all while getting meaningful practice with two- and three-digit addition and subtraction. No apps, no prep, no fuss.\u003c\/p\u003e\n\u003ch3\u003eQuick Details\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eGrade Levels:\u003c\/strong\u003e Grades 2–5 (best for 2nd–4th; great for advanced 2nd graders or 5th-grade intervention)\u003cbr\u003e\n\u003cstrong\u003eFormat:\u003c\/strong\u003e Printable PDF\u003cbr\u003e\n\u003cstrong\u003eResource Type:\u003c\/strong\u003e CSI Math Mystery worksheets\u003cbr\u003e\n\u003cstrong\u003eMath Skills:\u003c\/strong\u003e 2- and 3-digit addition \u0026amp; subtraction with regrouping, 10\/100\/1,000 more and less, adding multiple addends, true or false equations\u003cbr\u003e\n\u003cstrong\u003ePages:\u003c\/strong\u003e 28 pages including answer key\u003cbr\u003e\n\u003cstrong\u003eBest For:\u003c\/strong\u003e Valentine's Day, math centers, sub plans, early finishers, review, small groups, and homeschool math\u003cbr\u003e\n\u003cstrong\u003eTech Needed:\u003c\/strong\u003e None — no apps, locks, passwords, or student logins required\u003c\/p\u003e\n\u003ch3\u003eCase Summary\u003c\/h3\u003e\n\u003cp\u003eIt's Valentine's Day, and your students have worn their best clothes to school. The bell rings, they open their desks to grab their math books — and instead find an envelope with their name on it. Someone has left a secret valentine, and no one is owning up to it.\u003c\/p\u003e\n\u003cp\u003eGood thing your students are the chief inspectors for C.S.I. — Crime Scene Investigation. They tape off the desk, secure the surrounding area, and round up every suspect in the room. The only way to identify the secret admirer is to work the math.\u003c\/p\u003e\n\u003cp\u003eClue by clue, students add and subtract their way through the evidence: two- and three-digit problems with regrouping, more-and-less puzzles, true-or-false equations, and multiple addends. Each correct answer clears another name from the list until only one suspect is left holding the secret.\u003c\/p\u003e\n\u003cp\u003eHand your students the evidence, point them at the suspects, and let them prove they can crack the case. The math is the only thing standing between them and the truth.\u003c\/p\u003e\n\u003ch3\u003eSkills Covered\u003c\/h3\u003e\n\u003cp\u003eStudents will practice:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e2-digit addition and subtraction with regrouping\u003c\/li\u003e\n  \u003cli\u003e3-digit addition and subtraction with regrouping\u003c\/li\u003e\n  \u003cli\u003e10 more\/10 less, 100 more\/100 less, and 1,000 more\/1,000 less\u003c\/li\u003e\n  \u003cli\u003eAdding multiple addends\u003c\/li\u003e\n  \u003cli\u003eTrue or false addition equations\u003c\/li\u003e\n  \u003cli\u003eUsing answers to eliminate suspects\u003c\/li\u003e\n  \u003cli\u003eLogic, reasoning, and problem solving\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eWhat's Included\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eCSI-style math mystery activity\u003c\/li\u003e\n  \u003cli\u003eAddition and subtraction clue pages\u003c\/li\u003e\n  \u003cli\u003eMore-and-less and true-or-false puzzles\u003c\/li\u003e\n  \u003cli\u003eSuspect elimination activity\u003c\/li\u003e\n  \u003cli\u003eAnswer key\u003c\/li\u003e\n  \u003cli\u003ePrint-and-go PDF format\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch3\u003eBest Used For\u003c\/h3\u003e\n\u003cp\u003eThis printable CSI Math Mystery works well for:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eValentine's Day and February math activities\u003c\/li\u003e\n  \u003cli\u003eMath centers and early finishers\u003c\/li\u003e\n  \u003cli\u003eSubstitute teacher plans\u003c\/li\u003e\n  \u003cli\u003eSmall groups and independent work\u003c\/li\u003e\n  \u003cli\u003eHomeschool math\u003c\/li\u003e\n  \u003cli\u003eReview and reinforcement\u003c\/li\u003e\n  \u003cli\u003eAddition and subtraction practice\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Kiwiland Education","offers":[{"title":"Default Title","offer_id":61981846864242,"sku":"3607787","price":4.5,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0909\/2848\/0626\/files\/valentines-day-csi-math-mystery-addition-subtraction-grades-2-5-cover.jpg?v=1782501401","url":"https:\/\/kiwilandeducation.com\/products\/addition-subtraction-csi-math-mystery-worksheets-grades-2-5-the-valentines-surprise-card","provider":"Kiwiland Education","version":"1.0","type":"link"}