Putting together and taking apart! Once our students understand this, they will be successful at mental math!
So what does it mean to put a number together or take it apart?
Composing - putting together:
(standard form)
700+50+9 = 759
759 is compose of 7 hundreds, 5 tens, and 9 ones
Decomposing - taking apart:
(expanded form)
759=700+50+9
Kindergartners' standards K.0A.4 and K.0A.5 help our first grade students to understand 1.0A.6 - which states "add and subtract within 20...use strategies such as ... making 10" The students now know that making a ten helps in the addition process.
image from Donna Boucher Math Coach Corner
So what does it mean to put a number together or take it apart?
Composing - putting together:
(standard form)
700+50+9 = 759
759 is compose of 7 hundreds, 5 tens, and 9 ones
Decomposing - taking apart:
(expanded form)
759=700+50+9
Kindergartners' standards K.0A.4 and K.0A.5 help our first grade students to understand 1.0A.6 - which states "add and subtract within 20...use strategies such as ... making 10" The students now know that making a ten helps in the addition process.
image from Donna Boucher Math Coach Corner