Several basic principles about such geometric figures as points, lines, segments, and angles are selected and from these principles are derived many definitions, postulates, theorems, and finally logical conclusions. Skills in writing proofs are developed gradually. Simple discussing proofs are presented first, and next students study proofs written in two-column form. Students are helped to see the logical pattern of steps following previous statements and are asked to write simple proofs on their own. Thus experience is gained using the rules of reasoning and in writing proofs.