This is an interesting place value numeracy skill that has been added to the standards.
Students are asked to decompose so many ones...to tens and ones, etc. A little practice and students are really good at it. Use mini-lessons/spaced repetition for efficiency and effectiveness with this skill...recommended.
The most pragmatic is decomposing the hundreds. For example, 46 hundreds into its constituent discrete parts...4 thousands and 6 hundreds... 4,000 + 600 = 4,600. This is tough for elementary kiddos, but adults talk like this all the time...using this lingo for thosands values. It is good practice to understand it early on in school.
Best of luck...Blaine Helwig