The video supports the Common Core standard 2 NBT .9, explaining why addition and subtraction strategies work using place value and properties of operations. It covers related standards, the importance of using formal mathematical terms, and the principles of conservation and substitution. The video provides examples of addition and subtraction strategies, emphasizing the use of place value, commutative and associative properties, and mental math techniques.

What is the main focus of the Common Core State Standard 2 NBT .9?

• Understanding multiplication strategies

• Explaining addition and subtraction strategies using place value

• Learning division techniques

• Memorizing multiplication tables

Which related standard involves adding up to four two-digit numbers?

• 2 NBT 6

• 2 NBT 5

• 2 NBT 9

• 2 NBT 7

Why is it important to use formal terms like 'commutative property'?

• To avoid teaching simpler terms

• To make math more difficult

• To ensure students learn proper terminology early

• To confuse students

What does the conservation of number principle state?

• Numbers change when rearranged

• The number of objects remains the same when rearranged

• Numbers increase when rearranged

• Objects disappear when rearranged

How can place value help in solving addition problems?

• By ignoring the tens and hundreds

• By breaking problems into smaller parts based on place value

• By using only the commutative property

• By focusing only on the ones

What is the benefit of using commutative and associative properties in addition?

• To make problems more complex

• To rearrange numbers for easier computation

• To focus only on subtraction

• To avoid using place value

What is a key strategy for mental addition and subtraction?

• Avoiding mental calculations

• Memorizing all possible sums

• Ignoring place value

• Using estimation and checking reasonableness

How can converting numbers help in addition?

• By making calculations more difficult

• By ignoring place value

• By focusing only on subtraction

• By simplifying the addition process

What is a common approach to solving subtraction problems?

• Ignoring the ones place

• Decomposing numbers and using place value

• Avoiding subtraction altogether

• Focusing only on addition

What is an advanced technique for subtraction?

• Focusing only on addition

• Using only the commutative property

• Ignoring the tens place

• Breaking down numbers to avoid decomposing