Classify objects into given categories; count the numbers of objects in each category and sort the categories by count.1




Sorting objects and classifying them helps children to analyze commonalities and differences within sets. Students will be able to sort objects into given categories, as well as into their own categories, and be able to identify which category has the most objects, second-most objects, and so on.

Understanding the Standard:

  • Children should encounter exploration activities which ask them to reason what attributes objects within a set have in common with one another. Similarly, they should reason what differences they have as well.
  • The reverse concept is also important. Given a particular attribute, students should then find specific objects that can be grouped within that attribute set and similarly, be able to reason why other objects are not suitable for that attribute.
  • Ask students to sort objects into categories defined by the teacher (e.g, sorting candy by color), and specifically ask students to sort objects into their own categories.

Questions to Focus Instruction:

  • Can students explain the attributes that are associated with a specific set of objects?
  • Can students sort a group of objects according to a specific criterion or attribute?
  • Are students able to reason and explain why some objects cannot be grouped with a particular set?
  • Can students decide which of two categories has more objects? Which has the second-most, and so on?


Prior to: Students can determine how many items are in a set of objects.

At Grade Level: Students should be able to sort items and begin to communicate the reasoning for the way they have been sorted. Students can count the number of items in a particular category and make a general statement about that grouping in comparison to another set of grouped items.

Moving Beyond:
Students will separate a set of objects into many categories, and then clearly describe the reasoning for each grouping. When given data on a bar graph or a pictograph, students will be able to make generalizations about the information depicted in the graph.  Go to 1.MD.C.4 to see the progression of related skills.

1 Limit category counts to be less than or equal to 10.