NBT-Use+place+value+understanding+&+properties+of+operations+to+add+&+subtract

1.NBT.4. Add within 100, including adding a two-digit number and a one-digit number, and adding a two-digit number and a multiple of 10, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. Understand that in adding two-digit numbers, one adds tens and tens, ones and ones; and sometimes it is necessary to compose a ten. 1.NBT.5. Given a two-digit number, mentally find 10 more or 10 less than the number, without having to count; explain the reasoning used. 1.NBT.6. Subtract multiples of 10 in the range 10-90 from multiples of 10 in the range 10-90 (positive or zero differences), using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. || ===‍**Anchor Standard/Mathematical Practice(s)**=== 1.SE.1.1 Use technology hardware and software responsibly. 1.SE.1.2 Explain why safety is important when using the Internet. || ===‍ Revised Bloom's Level of thinking === Understanding-comparing numbers Applying- knowledge of numbers to compare numbers ||
 * ===**Common Core Standards**===
 * MP.2. Reason abstractly and quantitatively.**
 * MP.6. Attend to precision.**
 * MP.7. Look for and make use of structure.**
 * MP.8. Look for and express regularity in repeated reasoning.** ||
 * ===‍**Information Technology Standard**===

‍**I can...**
= I can compare numbers using <, > or =. = = = = I can compare numbers using greater than, less than and equal to signs. =

‍**Intervention:**
Use different colored chips to represent place values. (blue-100,red-10, yellow-1). Practice trading values when a group of 10 has been made. Count the days of school with a place value chart. Use toothpicks to make groups of tens and on. Play mystery number. Create greater than, less than to mouths. Have children illustrate inequalities with mouths. Use pretzels as greater than/ less than symbols. ‍**Enrichment: racecar game comparing numbers**

‍**Notes and Additional Information**
First Grade students use concrete materials, models, drawings and place value strategies to add within 100. They do so by being flexible with numbers as they use the base-ten system to solve problems. The standard algorithm of __carrying or borrowing is not an expectation nor a focus in First Grade__. Students are not expected to fluently add and subtract whole numbers using standard algorithms until the end of Fourth Grade. First Graders build on their work with tens and ones by mentally adding ten more and ten less than any number less than 100. First graders are not expected to compute differences of two-digit numbers other than multiples of ten. Ample experiences with ten frames and the hundreds chart help students use the patterns found in the tens place to solve such problems mentally. First Grade students use concrete models, drawings and place value strategies to subtract multiples of 10 from decade numbers (e.g., 30, 40, 50). They often use similar strategies as discussed in 1.OA.4.