A Tangram Heart for Valentines Day
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This Valentine’s Day, why say it with words when you can say it with maths? Let’s make a tangram heart and share some geometric love!
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A tangram is a puzzle consisting of seven flat polygons, which are put together to form different shapes. The seven pieces include two large right-angled triangle, one medium right-angled triangle, two small right-angled triangles, one square and one parallelogram. The triangles and the square both have reflection (or mirror) symmetry. That means, if you drew a line down the middle of them the two halves would be mirror images of each other. The parallelogram however does not have reflection symmetry, you can only get its mirror image by flipping it over. This means the parallelogram piece needs to be flipped to form some tangram puzzle shapes.
Tangram Heart Puzzle
Let's use the seven tangram pieces to create a heart! You can buy ready made tangram sets made of wood or plastic, so if you already own a tangram set you can use that to create a heart. For everyone else, we have prepared a tangram paper set that you can download, print off and cut out. The file 'Tangram Pieces (large)' has two sets per page, and 'Tangram Pieces (small)' has four sets per page. Whether you are using your own set or our paper set, the Tangram Heart Template will show you how to piece together a heart.
>> download Tangram Pieces (large)
>> download Tangram Pieces (small)
>> download Tangram Heart Template
The large tangram pieces are the same size as the heart template, so younger children can use this as a puzzle board to lay the pieces on top. Older children can try putting the heart together freehand.
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Remember what we said above, about the parallelogram sometimes needing flipped over? In our paper version, the parallelogram has the printed yellow side the right way up to make the tangram heart. But if you used these same paper pieces to make other tangram shapes, you might need to flip it over to the non printed side.
Tangram Heart Valentines Card
To make a tangram heart Valentines card, you will need:
- an A4 sheet of paper in a colour of your choice (we used pink)
- a print out of the 'Tangram Pieces (Small)'
- a pair of scissors
- a glue stick
- pens or pencils
You will also need the Tangram Heart Template as a guide.
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Step 1: Cut out the tangram pieces
Step 2: Fold your piece of paper in half to make an A5 sized card (the small tangram pieces are the right size to fit on this).
Step 3: Glue the tangram pieces to the front of the card, using the Tangram Heart Template as a guide
Step 4: Add a Valentines message with pens or pencils
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If you make your own Tangram hearts, we would love to see some photos. Please feel free to tag us in on Bluesky or Facebook, and use the hashtag #MathsWeekScot. You also enjoy some of our previous Valentines activities, including our Lego Hearts and the Geometric Heart Puzzle.
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