Estimate mass - math grade 2 - lesson 52

1.TEACHER SAY: Yesterday we learned about measuring the mass of objects. Let’s play Four Questions to review. I am going to ask four questions about measuring mass. You are going to take turns answering the questions with your Shoulder Partner.

STUDENTS DO: Take turns playing Four Questions with their Shoulder Partner.

TEACHER DO: Ask the following questions, allowing students time to share their answers with their partner:

• What two units do we use to measure the mass of objects?
• Are mass and weight the same thing? Explain.
• Which unit is used to measure objects with lower mass?
• Which unit is used to measure objects with higher mass?

TEACHER SAY: Great job reviewing. I have more items I want to share with you that will help us learn more about grams and kilograms. Today I have items that have a mass of about 1 gram, ½ kilogram, 1 kilogram, 5 kilograms, and 10 kilograms. Come up and stand in a circle.

Note to the Teacher: If there are too many students to form one large circle, have students form several smaller circles. You may use multiple examples of each item, or each circle may explore a different item at the same time. If necessary, substitute the items referenced in the lesson (and on your poster) as benchmark units with items that are more familiar to students.

STUDENTS DO: Stand in a circle with the class.

TEACHER DO: Display the poster you created of benchmark items.

TEACHER SAY: I am going to pass around each item so you can feel its mass. Hold it for a count of 5 and then pass it to your neighbor. As you hold it, think about how light or heavy it is. Some of the items are quite massive, so I will help you hold them. The name of each item and its approximate mass are on the poster here.

TEACHER DO: Point to the poster.

STUDENTS DO: Hold each item to feel the mass and count to 5. Then pass the item to their neighbor.

TEACHER SAY: Great job. I hope that helped you understand what different masses feel like. Let’s play a sorting game. First, find a partner using Hands Up, Pair Up. Once you have your partner, find a spot in the classroom to sit. I will hand out the game cards.

STUDENTS DO: Find a partner using Hands Up, Pair Up. Move to a spot in the classroom with their partner.

TEACHER DO: Take down the poster and hand out the Mass Matching Cards.

TEACHER SAY: You and your partner have a set of cards. You will work with your partner to match the items on the cards to their masses. Since you do not actually have the items, will have to use your critical thinking skills to estimate how heavy or light they might be. Remember that we are learning, so it is okay if you are not sure.You will put all of the items that have a mass of about 1 gram together, ½ kilogram together, 1 kilogram together, 5 kilograms together, and 10 kilograms together. At the end, you will have five different piles of pictures. Are you ready? You may begin.

STUDENTS DO: Work with their partner to sort picture cards based on the benchmark weights held and discussed today.

TEACHER DO: Walk around the classroom, offering help as needed. Allow students time to sort. When finished, go over correct answers with the class.

Note to the Teacher: As an extension activity, have students put their cards in order from least to greatest weight or greatest to least weight.