### Construct-o-straws

Make a cube out of straws and have a go at this practical challenge.

### Matchsticks

Reasoning about the number of matches needed to build squares that share their sides.

How can the same pieces of the tangram make this bowl before and after it was chipped? Use the interactivity to try and work out what is going on!

# Auditorium Steps

##### Age 7 to 14 Challenge Level:

Zaynab  from Parkhill Junior School wrote:

First of all I calculated how many squares there were of each colour.
Working out how many squares there were in the top part was the hardest as I had to make sure that I didn't overlap the squares.

In total there were:
Outer sides: 128 squares
Bottom: 64 squares
Top: 192 squares.

Within the top section, the colours were as follows:
Orange: 40
Green: 40
Purple: 64

I reduced the scale factor, and divided everything by 4. That way I could make a reasonably sized model. I drew it onto squared paper, then recreated it to make sure everything fit. I did this so that I could visualise it, as if I were really wrapping the auditorium.

Matthew from Dulwich College Suzhou in China sent in this picture:

Saksham from Hounslow Town Primary School sent in this picture:

Thank you for these good solutions that probably tested your visualising skills.