EXT K-2 Sampler

51 Lesson 10, 1ETeacherGuide 30 Objective 27: Touse a compensation strategy for adding 9 to anumber. Touse a function table to find basic fact sums. Topractice addition facts to 18. PD Materials: Base tenblocks, Addition-Subtraction Flashcards (Master 4) on yellowpaper, Addition- SubtractionMat (Master 3), BasicAdditionFacts (Master 15) ( see lesson plan p. 12 ) TheHungryBugStory Read the following story. Use base tenblocks to illustrate the bug’s stomach andpieces of fruit. Onceupon a time therewas a long skinnybug. Hismother calledhim ahungrybugbecausehe alwayswanted to eat until hewas completely full. Thehungrybug’s stomachheld exactly10 small pieces of fruit. Thebug’s stomach is the same size and shape as one tens block. Display 1 tens block. OnMonday, thebugwokeup and ate 9pieces of fruit for breakfast. Display 9ones cubes; place them in a rownext to the tens block. After breakfast thehungrybugwent for awalk to look formore fruit.He saw3pieces of fruit on the ground. Display 3ones blocks. Howmanypieces of fruitwill thehungrybug9 eat? (One piece of fruit.) Thehungrybug9will eat 1pieceof fruit so he canhave a full stomachof 10. (Move 1block into the bug’s stomach.) Howmanypieces of fruit are in thebug’s stomach andhowmany are left on the ground? (10 in the stomach and 2on the groundor 12 altogether. Continue the story for other days of theweek, asking students to take turns showing the bug’s stomach and the fruit on the ground. FunctionTables We canuse adrawingof a table to apply the patternor ruleof adding9 to anynumber. Writeon theboard: What is the sumof 9+5?What patterndid you use? (14; take 1 from the 5 andmake the 9 a 10) Ask students towork in small groups to complete the tables. Read the topof the page together, relating the IntroductoryActivity to the picture of the hungry bug. Add9 IN 5 6 8 4 7 9 OUT IN OUT Add9 Use base tenblocks todemonstrate how 9plus anynumberwill always be ten and 1 less than the number being added. For example, 9plus 5 is a 10plus a 4or 14.Write on the board: PreparingFlashcards DistributeAddition-SubtractionFlashcards (Master 4) printedon yellowpaper.Have students print one of eachof the following 21 facts on each Flashcard: 9+ 4, 8+ 5, 7+ 6, 6+ 7, 5+ 8, 4+ 9, 9+ 5, 8+ 6, 7+ 7, 6+ 8, 5+ 9, 9+ 6, 8+ 7, 7+ 8, 6+ 9, 9+ 7, 8+ 8, 7+ 9, 9+ 8, 8+ 9, 9+ 9. Have students use base tenblockunits and tens onAddition-SubtractionMats to find each sum and write the answer on the back. TicTacToeAddition: Skill Builders 27-5 Skill Builders 27-2, 27-3, 27-4, 27-7 30 ©Math TeachersPress, Inc.Reproduction by anymeans is strictly prohibited. Mental Math: HungryBug 9 Meet theHungry Bug. It always needs 10 cubes to be full. 2. 9 9 9 9 6 9 + 5 + 4 + 7 + 8 + 9 + 9 3. 4 . 1. 9 3 9 2 9 1 + 3 + 9 +2 + 9 + 1 + 9 9 + 3 is the same as 10 + 2 or 12. Howmany of these 3 cubesmust theHungry Bug 9 eat to be full? TheHungry Bug9 eats 1 of the 3 cubes to be a full 10. –1 +1 5. There are 5 cars in parking lot A. There are 9 cars in parking lot B. Howmany cars are there in all? __________ 6. There are 6 girls and 9 boys in the swimming pool. Howmany boys and girls are there in the swimming pool? __________ Add 9 3 6 5 Add 9 7 4 8 12 14 14 cars 12 13 11 16 11 17 10 15 15 boys and girls 10 18 12 15 14 16 13 17 HungryBugStrategy Grade1