Lesson Plan

• Apply binary addition rules to add multi‑bit binary numbers accurately.
• Perform binary subtraction using both the direct borrow method and the two’s complement technique.
• Analyse carry and borrow operations and explain their impact on result length.
• Convert a subtrahend to two’s complement and use it to subtract via addition.

• Projector or interactive whiteboard
• Printed worksheets with binary addition/subtraction exercises
• Binary truth‑table handout
• Set of binary number cards or flashcards
• Computers/tablets with a simple binary calculator app (optional)
• Markers and whiteboard

Begin with a quick “binary puzzle” on the board to spark curiosity about how computers add numbers. Review that students already know decimal addition and the concept of bits. Explain that by the end of the lesson they will be able to add and subtract binary numbers confidently and justify the steps they take.

1. Do‑now (5'): Students solve a simple binary addition (101 + 110) on the board to activate prior knowledge.
2. Mini‑lecture (10'): Explain binary addition rules and the carry table; demonstrate the example 1011₂ + 0110₂.
3. Guided practice (10'): Whole‑class step‑by‑step walkthrough of the addition example, students annotate each column.
4. Binary subtraction methods (15'): Present the direct borrow method (5') then the two’s‑complement method (10'), using the 10101₂ – 00111₂ example.
5. Independent practice (15'): Pairs work on the four practice questions from the source, teacher circulates to provide feedback.
6. Check for understanding (5'): Exit ticket – each student writes one binary addition or subtraction problem and its solution on a sticky note.

Recap the key steps for binary addition, borrowing, and two’s complement subtraction, highlighting how subtraction becomes addition in hardware. Collect exit tickets to gauge immediate mastery and address any lingering misconceptions. Assign a short homework worksheet requiring three additional binary operations to reinforce the day's learning.