EXT 3-6 Sampler

37 26 ©Math TeachersPress, Inc.,Reproduction by anymeans is strictly prohibited. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Multiplication facts can be foundby skip countingonanumber line. 2 groups of 4 become2 jumps of 4 ona number line. Multiplyingon aNumber Line Multiply. Use cubesonanumber line tomultiply. 1. 4 2=__________ 6 2=__________ 1 2= __________ 8 2=__________ 7 2=__________ 9 2= __________ 2. 5 3=__________ 3 3=__________ 4 3= __________ 7 3=__________ 0 3=__________ 9 3= __________ 8 3=__________ 1 3=__________ 6 3= __________ 3. 2 4=__________ 7 4=__________ 4 4= __________ 6 4=__________ 9 4=__________ 8 4= __________ 4. 3 5=__________ 7 5=__________ 4 5= __________ 8 5=__________ 5 5=__________ 9 5= __________ 5. There are 5 vases of flowers. Each vase has 9 flowers in it. Howmany flowers are there in all? __________ 6. There are 4 rows of cars. Each row has 5 cars in it. Howmany cars are there in all? __________ 2 4=8 Just callme theBigHopper! 8 16 15 21 24 8 24 15 40 45flowers 20 cars 12 14 9 0 3 28 36 35 25 2 18 12 27 18 16 32 20 45 Lesson8, 3ETeacherGuide 26 Objective20: Touse skip countingon anumber line to findmultiplication factswith factors of 0, 1, 2, 3, 4or 5. Materials: Interlocking cubes,NumberLine to81 (made fromMaster 6),marbles, pie tin PlasticCubes on aNumber Line Research suggests that themultiplication facts (and relevant division facts) shouldbe taught inmanageable groups. These lessonswill introduce the1s, 2s, and5s, then the3s and4s. Prepare a classnumber lineby taping together strips made fromMaster 6 asdoneonpage18. Each student shouldhave interlocking cubes. Let’s think of 3picturesof 3hands.Useyour cubes to showamodel of the3pictures. Put 5orange cubesonyourdesk. Put 5 cubesof adifferent colornext to them. Put 5 cubesof a different colornext to them.Howmany cubesdoyou have inall?Countby5s toget youranswer. (5, 10, 15) Have avolunteer bring3 trains of 5 cubes to theboard anddemonstrate that the cubes go to15on thenumber line. Sayanadditionproblemandamultiplication fact for thisproblem. (5 5 5 15 and3 5 15) Ask a student tohold the set of cubes above the5on the number lineon theboard and sayhowmany cubes are in1 groupof 5. Writeon theboard: 1groupof 5 5or 1 5 5 Ask a second student to join andhold another set of 5 cubes to the first set. (The second set of cubes,when joined to the first set, should cover the linebetween5 and 10.) Writeon theboard: 2groups of 5=10or 2 5=10 Repeat through9 5 45. Direct attention to the example at the topof thepage. Demonstratebyplacing2 trains of 4 cubes eachon the number line.Work several problemswith the class, showing students 2ways tomultiply: 1. Build towers of cubes and skip count. 2. Build towers of cubes andplace themon thenumber line. Listen andCount This activity improves listening skills. First, the teacher shields the activity as shedropsmarbles or cubes one at time into apie tin. Students countmentally.After the counting stops, they say andwrite thenumber ofmarbles in the can. Next, drop2 counters at a time into the tin. Students keep trackmentally andwrite amultiplication fact that tells thenumber of cubes in thepie tinwhen the counting stops. (For example, if youdropped3groups of 2 counters, then studentswouldwrite the fact 2 3=6.) After eachproblem, take the counters out of the container, one at a time, as you count them. Emphasize the landingpointswhenyou are counting. If youdropped2 counters into the can at a time, count 1, 2 , 3, 4 , 5, 6 , and so on. If appropriate, repeat bydropping3 counters at a time up to21, 4 counters at a timeup to20, and5 counters at a timeup to25. Skill Builders 20-2, 20-4, 20-10 3.OA.1, 3.OA.3, 3.OA.4, 3.OA.7 MultiplicationonaNumber Line Studentsusehands-on cubes tomakeanumber line. Students listen and check for one-to-one correspondence. Grade3