In this lesson, Miss Ramona Galea discusses important mathematical concepts including scale drawing, bearings, and angles of elevation and depression. Students are instructed on how to use the scale drawing method to calculate size and distance, emphasizing the necessity of tools like a ruler, protractor, and calculator. Practical examples are given, such as converting measurements with a scale where 2 centimeters is equivalent to 5 kilometers, to aid understanding of how these calculations apply in real-world scenarios.