Pre-K · Measurement & Data
PK.MD.2: Sort and count groups
PK.MD.2 is a Pre-K math standard in Measurement & Data. Here’s what it really covers, and how you can help your students learn it.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
The Pre-K math learning standard
Sort objects into categories; count the numbers of objects in each category. 1 (limit category counts to be less than or equal to 10)
In plain words
Sort and count groups.
Sample questions from student practice
These questions from Bobby's Math Club are the kinds of questions your students will see. You can try answering them to see what a student might see.
Question 1 of 3
How many apples do you see?
- 6
- 4
- 5
Where students can get stuck
- Changing the sorting rule partway through, such as putting a blue truck with the cars because it is a vehicle.
- Counting the whole pile instead of each group, and giving one total instead of a number per group.
- Leaving out objects that do not seem to fit, so the group counts do not add up to the whole.
Effective teaching strategies
- Ask students to say the sorting rule aloud before they begin, such as all the cars here, and recheck each object against that rule as it is placed.
- Point to each group after sorting and ask how many are in it, then write the count beside each group, keeping every group to 10 or fewer.
- Have students check that nothing is left in the pile, and ask about any object that did not seem to fit, so every object lands in a group.
Share it with families
Families can read Sorting things into groups and counting them for a plain-language look at this skill, with three questions to try together and ideas for helping at home.
Help every student practice measurement and data at home
In Bobby's Math Club, students practice at just the right level, with a hint when they need one, a clear explanation after every question, and kid-friendly videos. Unlimited practice is free for every family.
See how it works for teachers
Written by Robert “Bobby” Barnett
Bobby is an award-winning math teacher, the author of Meet Every Learner’s Needs, and the father of two elementary-school math learners. He uses Bobby’s Math Club with his own kids a few times every week. Learn more or contact Bobby.