Counting Large Numbers

We have been learning the best ways to count large numbers of objects. We began this when we were exploring the concept of 100 on the 100th day of school.
We had been counting groups of 10 by filling ten frames to count the first 100 days of school. Then we started counting other things by grouping them in 10s ( for example, the milk bags that we are collecting for Ms. Harris).

I gave the students a challenge to estimate if a collection of objects had more our less than 100 objects. Then they had to prove, and explain their answers ( we are working on explaining our answers in pictures, numbers, and/ or words - the writing in blue marker is how students explained their thinking to the rest of the class)

( we are trying to get away from ALWAYS counting by 1's -- with large numbers, it is easy to lose track of what number you are at, so if you have grouped your numbers into 10s, it is very easy to recount)

Next, we moved onto counting groups of objects by 5's (which we had already talked a bit about when counting tally marks). The importance of this skill will become more evident to the students when counting nickels because they can't count by ones to make five when counting nickels!