This lesson plan teaches students about percentage discounts over 90 minutes. Students will complete worksheets on fractions, decimals, and percentages. They will then work in groups to answer proportion questions and compute discounts on lawnmowers. Students will write checks, keep check registers, and present their work. The lesson ensures students understand discounts, discount rates, and discount prices. Formative assessments include worksheets and check activities. Summative assessments include the initial worksheet and homework on proportions.