Adding Rational Numbers Lesson: Signed Fractions & Decimals, Grades 7-8

Students who can add integers often freeze when the numbers turn into fractions and decimals. This lesson shows them that the same rules still work. Warm-up items review integer addition and add two positive fractions. Then a "same rules as integers" slide states it plainly: start at p and move the size of q, right if q is positive and left if it is negative; same signs add the sizes, different signs subtract them.

What's inside

• 17 slides, with speaker notes on all 17
• Lesson plan, 2 pages: standards, materials, objective, a teacher-guided sequence keyed to slide numbers, a "Watch For" note and a 25-minute version
• Scaffolded notes, 1 page, fill-in-the-blank to match the slides
• Practice worksheet, 2 pages: 18 practice items (10 adding, the first two on number lines; 5 in context; 3 find-the-error or explain)
• Exit ticket, 3 questions, two per sheet
• Answer key, 3 pages, with every step worked
• Print-all PDF, 9 pages: the lesson plan, the student pages and the answer key in one file

Answer key included

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