In this topic, students will:
solve real-world problems using properites of addition
identify patterns in the addition table and explain them using algebraic thinking
use mental math to add and subtract
use place value and a number line to round numbers
use rounding or compatible numbers to estimate a sum
use rounding or compatible numbers to estimate a difference
solve one-step and multi-step problems by modeling with math
Vocabulary:
Commutative (Order) Property of Addition - this property states that numbers can be added in any order and the sum remains the same
Identify (Zero) Property of Addition - this property states that the sum of any number and zero is the same number.
Associative (Grouping) Property of Addition - addends can be regrouped and the sum remains the same
Round - making a number simpler but keeping its value close to what it was (rounding to the nearest 10 or 100)
Compatible numbers - numbers that are easy to add, subtract, multiply, or divide mentally
Inverse operations - two operations that undo each other
Place value - the value given to a place a digit has in a number
At-home Practice:
Supplies:
a deck of cards
Divide the deck evenly between players. Decide if you're playing with 2 or 3 digits. Each player flips over 2 or 3 cards (depending on if you're playing with 2 or 3 digits). Each player rounds their number to the nearest 10 (or 100 if playing with 3-digits). The player with the largest rounded number wins all the cards. If players have the same rounded number, each player will flip over 2 more cards and round those. Continue playing until one player has all the cards. The player with the most cards wins the game.