Computer Science · 11th Grade

Active learning ideas

IP Addressing and Routing

Active learning works for IP addressing and routing because these concepts are abstract and hierarchical, making them difficult to grasp through passive methods alone. When students manipulate real network configurations, simulate packet forwarding, and debate protocol trade-offs, they build durable mental models that static lectures cannot provide.

• Common Core State Standards
• CSTA: 3B-NI-03

• 20–35 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Inquiry Circle
• 35 min · Small Groups

Inquiry Circle: Subnet Design Challenge

Groups receive a network specification (number of hosts per subnet, address range) and must design a valid subnet scheme using CIDR notation. Groups exchange their designs and verify each other's calculations, then discuss any discrepancies and identify the most efficient approach.

Explain the function of IP addresses and subnet masks in network communication.

Facilitation Tip

During the Subnet Design Challenge, circulate with a copy of the CIDR chart and ask each group to explain their subnet boundaries aloud before submitting their final design.

What to look for

Provide students with a list of IP addresses and subnet masks. Ask them to calculate and write down the network address and broadcast address for each. Review answers as a class, addressing common errors.

• Analyze
• Evaluate
• Create
• Self-Management
• Self-Awareness

Activity 02

• Role Play
• 25 min · Whole Class

Role Play: Human Router Simulation

Each student holds a routing table card listing network prefixes and next-hop addresses. The teacher acts as a data packet and calls out a destination IP. Each router student decides the next hop for that destination based on their table, and the class traces the packet's path across the room until it reaches the correct destination or gets dropped.

Analyze the process of routing data packets across different networks.

Facilitation Tip

For the Human Router Simulation, assign one student to act as the routing protocol observer and give them a clipboard to record updates to the routing table after each topology change.

What to look for

Pose the question: 'Imagine you are designing the IP addressing scheme for a new school with 5 departments, each needing about 50 IP addresses. How would you use CIDR notation to allocate addresses efficiently? What challenges might arise?' Facilitate a class discussion on their proposed solutions.

• Apply
• Analyze
• Evaluate
• Social Awareness
• Self-Awareness

Activity 03

• Think-Pair-Share
• 20 min · Pairs

Think-Pair-Share: IPv4 vs. IPv6 Trade-offs

Present the constraints that drove IPv6 adoption and the challenges of the transition period. Students individually list three advantages and two practical challenges of IPv6, then compare their lists with a partner and refine before a class discussion that weighs the adoption timeline.

Differentiate between IPv4 and IPv6 and their respective advantages.

Facilitation Tip

In the IPv4 vs. IPv6 Trade-offs discussion, provide a Venn diagram template so pairs can organize their arguments visually before sharing with the class.

What to look for

On a slip of paper, have students write one key difference between IPv4 and IPv6. Then, ask them to describe in one sentence how a router uses a routing table to send a data packet to a computer on a different network.

• Understand
• Apply
• Analyze
• Self-Awareness
• Relationship Skills

Activity 04

• Gallery Walk
• 30 min · Small Groups

Gallery Walk: Routing Protocol Comparison

Post summaries of three routing protocols (RIP, OSPF, BGP) at different stations. Student groups visit each station, annotate the key features and appropriate scale, and on a central whiteboard map which protocol fits which network scenario. The class debrief connects protocol choice to real-world network architecture.

Explain the function of IP addresses and subnet masks in network communication.

What to look for

Provide students with a list of IP addresses and subnet masks. Ask them to calculate and write down the network address and broadcast address for each. Review answers as a class, addressing common errors.

• Understand
• Apply
• Analyze
• Create
• Relationship Skills
• Social Awareness

A few notes on teaching this unit

Teachers should avoid treating IP addressing as a purely mathematical exercise. Instead, ground every calculation in a real-world scenario, such as designing a school network or troubleshooting a failed connection. Research shows that students retain concepts better when they see how addressing and routing decisions affect actual devices and users. Use analogies carefully, as misleading comparisons (like comparing IP addresses to phone numbers) can reinforce misconceptions about permanence and scope.

Students will demonstrate understanding by designing functional subnets, accurately routing packets in a simulation, comparing protocols with evidence, and explaining trade-offs between addressing schemes. Success is visible when they move from procedural recall to strategic problem-solving in network design.

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Watch Out for These Misconceptions

• During the Subnet Design Challenge, watch for students who treat the IP address as a permanent identifier like a MAC address.

  During the Subnet Design Challenge, have students examine their DHCP server logs or lease tables from the lab setup to see how IP addresses are assigned dynamically and can change with each connection.

• During the Human Router Simulation, students may assume routing tables are static and never update.

  During the Human Router Simulation, introduce link failures or new network segments mid-simulation to force students to recalculate routes and update their tables, making the dynamic nature of routing visible.

• During the Gallery Walk activity, students might visualize the internet as a single flat network.

  During the Gallery Walk, direct students to map the AS numbers and prefixes they see on the posters to real-world autonomous systems, highlighting the hierarchical structure of the internet.

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Methods used in this brief

• Inquiry Circle
• Role Play
• Think-Pair-Share
• Gallery Walk