Revisit the word wall, class science journal and learning from Lesson 3. Discuss how students described materials using the words “stiff” and “bendy”.

Remind students that materials have properties, which are the ways the materials look or behave when they are tested by scientists.

Remind students of the tests they watched in the previous lesson (involving the stiff material and a tissue) that showed that stiff materials can hold things up, but bendy materials cannot. Repeat the demonstration if necessary.

Ask students to consider whether they think a tissue on a skewer could be called a “shelter”, and why or why not.

Ask students to think about any shelters built for people that they have seen/identified, such as umbrellas, tents, cubbies and shade shelters. Use images from earlier lessons to support students’ comments or ideas.

Discuss how these shelters are different from a tissue on a skewer. Identify what makes a shelter stand up by itself, and ask students to consider what might make a shelter fall over in the wind. Record ideas in the class science journal.

As part of the conversation, guide students towards the following ideas:

• A frame needs a shape.
• A frame needs a base.
• A frame needs to be big enough to fit a living thing, but not too tall, particularly in comparison to the size of the base.
• The joins between materials need to be strong.
• The frame needs to be weighted or attached to the floor or ground.

Demonstrate for students that the number of pieces in a frame matters too, using a few loose materials. For example, place one stick upright and show that it falls over, and/or show how two sticks joined together cannot stand up on their own. Then show the simple joined structure (prepared as part of the materials list) and discuss whether it stands more easily and why. Explain that shape matters, not just material: a triangular base made with three skewers, or a square base made with four skewers, will stand up by themselves.

Ask: What might help a frame stay still in wind? Students may suggest a wide base, strong joints, a lower height, a weighted base or being secured to the ground.

Try out student suggestions to explore the stability of a narrow base compared with a wide base and secure joints compared with insecurely linked joints.

Pose the question: What are the best shapes and materials to help a shelter stay up by itself?

Explain that students will now build and test a shelter frame for one of the toy characters discussed earlier in the sequence.

Work with students to list the things that will make a good frame. For example:

• The toy will fit inside the frame.
• The frame will stand up by itself.
• The frame will stay still in the wind.

Explain that today the class is only testing whether the frame structure works as it is supposed to. Explain that teams will build their frame and test it by:

• fitting the toy inside the frame.
• making sure the frame stands up on its own.
• making sure the frame doesn’t blow away in the wind, by placing it in front of an electric fan to replicate the wind in a storm.

Give each team the required equipment: one toy, one type of frame material, and masking tape strips.

Model how to make a square pyramid as an example of a shape that teams could use for their frame. Keep the modelling brief so students still do the building themselves. Emphasise that the frame does not need a cover yet.

Model how to record students’ ideas and testing results using a demonstration copy of the Frame testing Resource sheet.

Teams build their frames. Encourage them to test whether the toy fits inside and whether the frame stands up by itself as they build. Encourage students to make adjustments to ensure their frame meets these two criteria as they go. Teams record the results of these two tests on the Frame testing Resource sheet.

In the following Integrate routine, students are guided to link their experiences of building and testing their frames with the science concept being explored: stiff materials are more suitable than bendy materials for building a strong frame. Through modelling, questioning and discussion, students should come to a consensus that: stiff materials can stand up by themselves. when connected together, stiff materials can make a strong frame. a wide base makes a frame more stable.

When all teams have assembled their frames, test each one using an electric fan to simulate wind so that students can observe whether each team’s shelter stays stable. Use the same fan setting, and place the frames at approximately the same distance away from the fan so the test is as fair as possible. Encourage students to watch each frame test carefully and describe what happens.

Allow teams time to record the results of their wind test on their Frame testing Resource sheet.

Discuss each frame and why it did or did not stay stable.

Note: Sensitivity may be required here, as younger students may take feedback as personal criticism. Discuss with students beforehand how an important aspect of working like a scientist is testing ideas and making improvements. Including positive feedback, as well as areas for improvement, can help students feel less overwhelmed when their frames are tested.

Look at each of the materials used to make a frame and ask students if they think the material could hold up something heavy and why they think that.

Show students some objects that can act as weights, including some that are light and some that are heavier, and ask if they think each object would be able to balance on each frame without the frame bending or breaking.

Optional: Test some of the students’ frames to see if they can hold up the different objects.

Identify which part of a shelter the weight represents (the cover).

Compare what students noticed across the different material groups and help them to identify patterns. For example:

• Some materials bend more easily.
• Some frames stand well until the fan is turned on.
• Some frames are too tall and tip over.
• Some frames need stronger joints or a wider base.

Record a statement based on the class’s observations to answer each of the following questions about the ideal frame:

• The best frame material is ____ because ____?
• Why does the ideal frame need to fit over the toy?
• Why does the ideal frame need to stand up?
• Why does the ideal frame need to stay still in the wind?
• What kind of base does the ideal frame need? Why?

Reinforce that the frame needs to do all these things before a cover is added, because the frame is needed to hold up the cover and make it wide enough for something to shelter under. Connect this to real shelters and umbrellas: the structure underneath (the frame) is important.

Co-construct a class statement such as: A good shelter frame needs to fit the toy, stand by itself, and stay steady in the wind.

Discuss and record practical improvements students could make before the final shelter testing. These may include:

• making the base wider.
• making the frame shorter.
• strengthening the joints.
• adding weight to the base.
• securing the base to the ground.

 

Reflect on the lesson  

You might:

• review the class science journal.
• revisit the meaning of “frame”, “self-supporting” and “stable”.
• add new words and any related drawings or photos to the word wall.
• review what students have learned about wide bases, lower heights, strong joints and stable shapes.
• discuss which materials were easiest or hardest to build with.
• ask students to show or explain one change they would make to improve their frame.