This book has recorded the initial simulation of the construction behaviour of young children. It includes the children's construction skills from simple to difficult, the progression of two-dimensional to a three-dimensional structure, and their spatial thinking and representation abilities. This project was conducted for approximately four-and-a-half months. It was started by a group of children who showed great interest in constructing different buildings at the constructive corner. The teacher then introduced the picture book of [Iggy Peck Architect], which led children to discuss more buildings that they are interested to build. This project was then carried on beyond the classroom, whereby children were given the opportunity to do their research from field trips. This first-hand experience has become an important scaffold in supporting the children's learning and also stimulating their thinking toward the design of building structures.