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TWI takes ‘Welding with Chocolate’ to Rodings Primary School

Mon, 08 April, 2019

On the 4th of April, 2019, TWI presented its famous ‘Welding with chocolate’ activity at Rodings primary school in Essex. The workshop was led by TWI employee Matthew Haslett and assisted by TWI apprentice Bethany Richards, alongside NSIRC students Jessica Taylor and Pedro Santos.

In this activity, basic technical principles related to welding, testing, materials and construction are presented and discussed throughout the sessions, challenging the children to think in a scientific manner. Fundamental welding principles are demonstrated using hot water in a glass bottle as the heat source and chocolate bars as the welding material. The children weld 4 chocolate bars together to make a small box girder bridge, making the box shape much stiffer than a single bar. After solidification, the box girder bridge is destructively tested by adding weights to their mid-span. The maximum load is then recorded and compared against the maximum load recorded for a single chocolate bar. "I can't believe we made it so strong!", as said by 6 year-old Jorge, is the most common reaction from students and teachers after testing the box girder.

Welding with chocolate is an innovative and fun hands-on activity exploring welding principles and mechanical testing in the classroom or at home. Miss Ducat, one of the year 1 teachers expressed her views on the workshop by saying: "The workshop was just brilliant...great fun and everything was really clearly explained, just at the right level for the children."

As part of TWI’s education outreach activities since 2007, Welding with Chocolate is generally suitable for children from reception (4 years of age) up to lower secondary (14 years of age) but can be tailored to suit older children as well. This activity has been run at numerous events in the past few years, ranging from school science days to national events such as the Big Bang Fair and other STEM events.

Volunteer quotes:

“As a volunteer, it’s a very rewarding activity to take part in: the children are always amazed at the strength of the chocolate bridges and the loud ‘bang’ as the bridges collapse!” – Pedro Santos

“I love seeing the kids, some as young as four years old, really engaging with the workshop and learning something about engineering – that makes it worthwhile for me.” – Jessica Taylor

“For me, it’s lovely to work with the kids as they are always enthusiastic to get involved and very kind to the adults. As a scientist, I learn something new about engineering every time!” – Bethany Richards

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