Abstract Children observe and interact with two-dimensional and three-dimensional objects through everyday activities in the environment such as building blocks, books, balls, or puzzles. Learning geometry is one of the outcomes of Victoria's Essential Learning Standards. Geometry offers students the opportunity to engage in mathematical thinking that allows them to make conjectures. This report will reflect the lesson plan in four areas: • Key mathematical ideas and skills. • Link to relevant teaching materials and understanding of the learning sequence. • Teaching approaches, developing children's understanding, appropriate models and materials for learning.• How children learn math concepts.1. Key Mathematical Ideas and SkillsGeometry is a branch of mathematics that involves the study of the properties of points, lines, planes and curves, shapes and solids (Booker et al. 2010, pp. 395). It is applied in broad fields of knowledge such as graphics, design, art and geography. The point of space for elementary school children is to learn common two-dimensional figures and three-dimensional solids by exploring a variety of objects in the environment. Children are encouraged to participate and practice teamwork through activities. It helps them improve skills such as visualizing, explaining, thinking, recording and drawing, as well as mathematical language. According to the Victorian Essential Learning Standards, there are two forms of geometry that children study in primary school. Visual geometry: it engages children. in the use of space, shape and form through symbolic representation, intuitive and personal level (Booker et al. 2010, pp. 396). The mathematical language used in this area is natural and informal...... middle of sheet ......d variety to the range encountered by children.• Describing activities and relationships: By having to use the language , children begin to clarify and connect what they learned from the activity with what they already know. Thinking through the use of written and oral language is an important feature of developing understanding of geometric concepts. The teacher should provide children with open-ended tasks and questions for reasoning and explanation rather than for memory checking.4. How Children Learn Math ConceptsAccording to Piaget's stages of cognitive development, children between the ages of two and seven begin to have a symbolic representation of the present and reality. They prepare you to understand concrete operations. Language and imagination are used to expand their thinking skills and understand the world around them. At stage 7 – 12 years