are two different processes of addition Knowledge that “taking apart” and “taking from” are two different processes of subtraction appropriate terminology and symbols which include “+,” “–,” and “=”. Addition terminology: add, join, put together, plus, combine, total Subtraction terminology: minus, take away, separate, difference, compare Students may use document cameras or interactive whiteboards to represent the concept of addition or subtraction. This them the opportunity to communicate their thinking. Standard: K.OA.A.2 Solve addition and subtraction word problems, and add and subtract within 10, e.g., by using objects or drawings to represent the problem. Essential Skills and Knowledge Ability to represent the process of solving various types of addition and subtraction word problems (CCSS, Page 88, Table 1) within 10 using objects and drawings to develop number sentences Knowledge of the different types of word problems (e.g., add to, result unknown; take from, result unknown; put together/take apart, total unknown) which lays the foundation for more difficult word problems Using a word problem context allows students to develop their understanding about what it means to add and subtract. Addition is putting together and adding to. Subtraction is taking apart, taking from, and comparing. Kindergarteners develop the concept of addition/subtraction by modeling the actions in word problem using objects, fingers, mental images, drawings, sounds, acting out situations, and/or verbal explanations. Students may use different representations based on their experiences, preferences, etc. They may connect their conceptual representations of the situation using symbols, expressions, and/or equations. Students should experience the following addition and subtraction problem types (see CCSS, Page 88,Table 1). Add To word problems, such as, “Mia had 3 apples. Her friend gave her 2 more. How many does she have now?”
The student tosses ten two-color counters on the table and records how many of each color are facing up. Standard: K.OA.A.5 Fluently add and subtract within 5. Essential Skills and Knowledge Ability to decomposition knowledge and relationship between addition and subtraction to determine the sum or differences of various problems This standard focuses on students being able to add and subtract numbers within 5. Adding and subtracting fluently refers to knowledge of procedures, knowledge of when and how to use them appropriately, and skill in performing them flexibly, accurately, and efficiently. Strategies students may use to attain fluency include: Counting on (e.g., for 3+2, students will state, “3,” and then count on two more, “4, 5,” and state the solution is “5”) Counting back (e.g., for 4-3, students will state, “4,” and then count back three, “3, 2, 1” and state the solution is “1”) Counting up to subtract (e.g., for 5-3, students will say, “3,” and then count up until they get to 5, keeping track of how many they counted up, stating that the solution is “2”) Using doubles (e.g., for 2+3, students may say, “I know that 2+2 is 4, and 1 more is 5”) Using commutative property (e.g., students may say, “I know that 2+1=3, so 1+2=3”) Using fact families (e.g., students may say, “I know that 2+3=5, so 5-3=2”) Students may use electronic versions of five frames to develop fluency of these facts.