Students first listen to a story about sorting buttons and discuss various sorting attributes used. Then they explore the concepts of alike and different as they compare objects. Finally, students use sorting rules to make groups and also observe groups to name the sorting rules. Extensions of the lesson allow students to explore ways that outcomes of events can be applied to sorting objects.
Introduce this lesson with a review of the concepts of similar and different. Place an assortment of classroom materials, such as pens, pencils, crayons, blocks, and small toys in a bag. Take two objects and ask, “How are they similar? How are they different?” Encourage a variety of responses. Take out another object and ask what is the same and different about that object and one of the previous objects. Ask students to take turns removing objects from the bag and giving a variety of ways the new object is like or different from one or more of the objects that were previously removed from the bag.
Transition students from the discussion to the book 3 Little Firefighters by Stuart J. Murphy.
“I have a story to share with you. It’s about some firefighters who need to find buttons for their coats. When I’m finished reading I will ask you to tell me how the buttons they chose were alike or different.”
Other storybooks such as the following could be used to introduce sorting and to demonstrate sorting by attributes: Cat Show by Jayne Harvey, Dave’s Down to Earth Rock Shop by Stuart J. Murphy, Let’s Sort by David Bauer, Turn the Wheel Shapes and Sorting by Roger Priddy.
Read the story and ask students to share what they noticed about the buttons the firefighters used and how they sorted them into sets. (Note: If you use one of the alternative storybooks about sorting, students should identify one way the objects in that story were sorted.)
Create a class poster (attribute anchor chart) with the different ways the characters sorted. Continue to add to this poster throughout the unit. (Students may say: They tried sorting the buttons by color, but they didn’t have enough for their coats. They sorted by shape, but they still didn’t have four each so they had to sort by size, and that worked!)
“You were really paying attention. The firefighters had a collection of buttons that they sorted by three different rules. They had to keep sorting the buttons until they found enough that were alike in some way. Now let’s look again at the collection of things in our bag and figure out ways they can be sorted.”
Take two unlike objects out of the bag, such as a pair of scissors and a roll of tape. Students may find it easier to begin describing the objects by their differences. (The scissors cut things apart, but the tape puts things together. The scissors and the tape are different shapes and colors.)
Encourage students to continue by finding something about the objects that is alike. (The tape has a hole in the middle like scissors have holes in the handles.)
“Good observation. Both of these objects have holes through them.”
Continue the activity by passing the bag to students one at a time, having them each take out an object. Give each student time to describe the object and what is alike or different about it when compared to the previous object. Let’s say the next student takes out a glue stick. (My glue stick is sticky. The tape is also sticky. But my glue stick doesn’t have a hole.)
“That’s right. Your objects are alike because they are both sticky. The glue stick does not have a hole like the scissors or the tape.”
If students have difficulty finding a similarity, prompt them to look for sides that are flat, shared colors (both have red on them), shared purpose (they both write), whether the objects will roll, if they have words, etc. Help them notice several attributes of each object. This will help them in the sorting activities that follow.
When all students have had a turn taking an object out of the bag and making comparisons, have them keep the object for the next sorting activity.
Choose one of the likenesses suggested by students and have the class sort their objects into two groups, those that have the attribute and those that do not. Make two large circles on the floor with string or hoops to define the groups (e.g., those that write, those that don’t).
Say, “I’m going to choose a rule that will help us sort our objects in a new way. We are going to make two groups again. This circle is for objects that we use to write, and this circle is for objects that do not write.”
Give each student a turn to put his/her object in the correct group, explaining why that group was chosen. (Students may say, My pencil writes, so it goes in this group. This block doesn’t write, so it goes here.)
Once all of the objects have been sorted, return them to the mystery bag and play a sorting game called Guess My Rule. Think of a rule that describes some, but not all, of the objects in the bag. Do not share your rule.
“I am thinking of a way that some of these objects are alike. We’re going to pass the bag again and you will take an object out. Show me your object and I will tell you if it fits my rule. If it does, you’ll put it in this circle. If it does not, you’ll put it in this one. I want all of you to think quietly about what you think my rule is. Don’t say it out loud until I ask for guesses.”
Pass the bag again, giving several students a turn to pull out an object. Stop when several objects have been placed in the groups and encourage students to guess the rule. If the guesses are incorrect, continue sorting objects.
When the correct rule is guessed, place the objects back in the bag and have the student who guessed the rule choose the sorting rule for the next game. Guide students in choosing rules that are specific and obvious. A rule about the sizes of objects, for example, would be difficult when using classroom objects that are not clearly large or small.
Play the game again, as time allows, giving more students a chance to pull an object out of the bag.
Evaluate students’ progress using a checklist (M-K-5-2_Sorting Observation Checklist.doc).
Each time the class correctly guesses a rule, take time to look at a few objects in each group and ask students to identify the attributes that either fit the rule or do not. Observe whether students can identify attributes and justify the inclusion of objects in one group or the other.
This activity could be extended by using two sorting rules; for example, separate objects that roll and objects with flat sides. When students discover that some objects roll and also have flat sides, such as a crayon, lead students to suggest new ideas for organizing groups. An overlapping Venn diagram could be introduced if students demonstrate readiness to increase the complexity of sorting rules.
Extension:
Use the activities and strategies listed below to tailor the lesson to meet the needs of your students during the year.
- Routine: This activity could be done frequently at a regular time of the day, such as before math time, or would work well as a transition activity when you have a few extra minutes before recess or lunch.
Think of a rule that would sort students into two groups, but do not announce the sorting rule. For example, you might choose students wearing long sleeves and students wearing short sleeves. Choose students one at a time to stand in front of the class, putting them in one of the two groups. When several students are standing, have others in the class guess your rule. If they are correct, the activity stops. If they are wrong, sort more students into the groups until the rule is guessed correctly. Observe student participation and how quickly each student catches on to assess those who might need remediation to strengthen the key ideas of sorting and classifying.
Make the activity more challenging by choosing a secret rule and letting only two students stand in each of the two groups. Ask a volunteer to choose which group to stand in and explain why s/he chose that group. If the volunteer chooses the correct group according to your secret rule, ask him/her to choose another student who fits in the same group. If the volunteer is not correct, call on another student to choose a group and guess the rule. Continue until the rule is discovered.
- Expansion: Use the mystery bag again for this activity. Remind students that the objects were collected from the classroom and have been sorted in many ways. Tell students that this time, you will name an attribute and ask them to tell whether it is likely, unlikely, certain, or impossible to pull something from the bag having that attribute.
“If I reach into the bag without looking, how likely is it that I will pull out a classroom item?”(It is certain. Everything in the bag is something from the classroom.)
“How likely is it that I will pull out a steam iron?” (That is impossible.)
“Why do you think that?” (Because we didn’t have an iron in the classroom when you put things into the bag.)
“Is it likely or unlikely that I will pull something out of the bag to use in an art class?” (That’s very likely because most of the things in the bag are things that we use in art.)
As students become more familiar with this activity, challenge them to think of their own questions to ask about objects that are likely, unlikely, certain, or impossible to pull from the bag.
- Small Group: Provide students with a handful of Backyard Bugs counters or other set of classroom manipulatives that can be sorted by two or more attributes. Ask students to select a rule and sort the bugs into two groups. Observe students as they work to see whether they sort by one or two attributes. Does their rule sort bugs into two distinct groups (dragonflies and spiders), or do they have overlapping sets (red bugs, caterpillars, and red caterpillars)? Do their sets clearly follow the sorting rules? Can classmates guess the rule?
