World of Tan 16 - Time flies
Can you fit the tangram pieces into the outline of the candle?
Problem
This activity follows on from World of Tan 15 - Millennia.
Granma T and Mah Ling are sitting together during a lull in the afternoon, when all the big tasks for the day have been done and only a few small jobs still need completing. They are finishing off the day's work and preparing for tomorrow over a warming cup of tea.
Granma T: Doesn't it feel nice to sit down for a few minutes? It's been so busy during the New Year, with all the festivities and the cleaning taking up most of our time.
Mah Ling: This is my favourite time of year - the few days after the Festival of Lanterns when we can start looking forward to the year ahead.
Granma T: More and more often, I find myself looking back instead of forwards. For instance, surely it can't have been a whole year since the last Festival of Lanterns?
Mah Ling: I know, it only feels like yesterday that we were celebrating the start of the Year of the Dragon, and now we're already into the Year of the Snake! When I was little, time seemed to drag...
Granma T: ...But now that we're getting older, it feels like time keeps speeding up. Celebrating the start of a new year serves as a good reminder that time flies.
Mah Ling: That reminds me, there's only a few minutes left to get your letters in the post!
In the meantime, complete the silhouette of the candle.
Extra activities:
- Try this activity to see if you can estimate how long a minute is. Sit down and ask your friend to carefully time a minute. When you think one minute has passed, stand up. How close were you?
- Repeat the experiment. Was your estimate closer to a minute? How can you improve your estimate?
The story continues in World of Tan 17 - Weather.
Teachers' Resources
Why do this problem?
This problem is an engaging context in which pupils can consolidate their knowledge of the properties of squares, triangles and parallelograms. By attempting this activity, children will be putting into practise their visualising skills, making guesses about where the different shapes might go before trying out their ideas. When combining the shapes to make the tangram, pupils will use their understanding of translations, reflections and rotations to decide how to transform each shape. There are also links between tangrams and fractions, and children can be encouraged to work out what fraction of the whole square is represented by each smaller shape.
Possible approach
Read this story with the whole class and look at the tangram as a group. Ask pupils to suggest where a shape might go. What transformation would be needed to move the shape into that position?
When pupils are solving the tangram, they would benefit from working in pairs with a tablet or a printed copy of the shapes to cut out and move around. Working together will lead to rich discussions about the possible options for where each shape can go. When the children have solved the tangram, they can have a go at the extra activities.
At the end of the lesson, bring all of the pupils together and model the solution on the whiteboard. How does each shape need to be transformed? What fraction of the whole picture is each shape?
Key questions
What could you put with this piece to make a square?
Are all of the pieces different?
What's the smallest square you can make?
What has to go in that space? How do you know?
Possible extension
Pupils could have a go at other tangrams in the 'World of Tan' series. Some children might like to create their own tangram from the same pieces, or make their own tangram pieces by cutting up a square.
Possible support
Some children might need encouragement to experiment and 'have a go'. Using the printable tangram pieces will help all pupils try out their ideas.