How Much Does It Weigh?
Students will be able to classify objects as heavy or light.
- Gather students together for the lesson.
- Hold up two objects (a feather and a rock) and ask students if they know which is heavier and which is lighter.
- Pass the objects around the class and have students share out their ideas (e.g. the feather is lighter than the rock because I can feel it, etc.).
- Explain that today they will be learning all about comparing objects to see which is heavier and which is lighter.
Explicit Instruction/Teacher modeling(10 minutes)
- Read aloud the text, Who Sank the BoatTo the students.
- Hold up the two objects from the introduction and model thinking aloud to differentiate between the two, e.g. "I have to work harder to hold the rock. The feather feels lighter in my hand, it might float away on its own."
Guided practise(15 minutes)
- Display the balance and explain that we can use a balance to compare two objects to determine which is heavier and which is lighter.
- Model how to place items in each cup of the balance and note what happens to the cups (one side moves up while the other side moves down).
- Display two more objects (heavy/light) and ask students to PredictOr make a guess using what they know, to decide which item is heavier and which is lighter than one another.
- Pair students together and pass out a balance and some objects to each pair. Have students practise making predictions, and then comparing the items to determine which is the lightest and which is heaviest.
- Ask students to think about which item is heavier and which is lighter. Say, "How can you tell?"
- Gather students back together and hold up an object (e.g. a pencil). Say, "Can you find something that is lighter than this pencil? How about something that is heavier? How about something that weighs the same?"
- Allow time for students to find objects and share with a partner.
Independent working time(5 minutes)
- Explain that now students will get to identify things that are heavier and lighter than something else.
- Display the Comparing: Heavy vs. LightWorksheet and go over the instructions.
- Pass out the worksheets and have students complete them independently.
- Provide additional practise by previewing the target vocabulary with students prior to the start of the lesson.
- Work with a smaller group of students to explore wooden blocks. As students explore the blocks, observe their work and introduce new vocabulary to describe their actions, e.g. "Ann put 2 of the blocks together. I wonder which is lighter, this tower or this single block over here?"
- Display images of items and work with students to sort them into categories of heavier or lighter than a given object (e.g. a cow).
- Encourage students to think about how weight might be related to size. Provide students with additional objects such as a toy animal and a kitchen sponge of approximately the same size.
- Ask students to predict which item is heavier or lighter before they weigh it or pick it up.
Review and closing(5 minutes)
- Gather the group back together and provide additional practise using the new vocabulary words by displaying an object and saying, "This cup is heavier than ________" and having students finish the sentence.