Welding with Chocolate is a fun hands-on activity exploring welding principles and mechanical testing and is one of TWI’s education outreach activities. It was developed in 2007 and aims to enthuse school children about Science, Technology, Engineering and Mathematics (STEM) subjects. It 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.

Basic welding principles are demonstrated using a heat source of hot water in a glass bottle and chocolate bars as the material. The children weld 4 bars together to make a small box girder bridge. The bridges are then destructively tested by adding weights to their mid-span and compared against the strength of a single bar. Basic technical principles related to welding, testing and construction are presented and discussed throughout the sessions. The children are always amazed at the strength of the chocolate bridges!

Welding with Chocolate has been run at hundreds of events in the past few years, ranging from school science days to national events such as the Big Bang Fair.