How a Message Crosses the Internet

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Technology and Computer Science · Computer Science
SP-CS-008 · Free to print and use in your classroom · substituteplans.com
Page 2
How a Message Crosses the Internet
Technology and Computer Science · Computer Science · Grades 7-10 · 50 minutes
Time needed
50 minutes (one class period)
Prep
Copy the 2-page worksheet (one per student). No board work is needed.
Technology
None.
Student
independence
High. Students read and answer independently, then compare the packet puzzle with a
partner.
Copies to make
One 2-page worksheet per student
Materials
Pencils, Worksheet
Goal for today: Students will explain in plain words how data travels as packets across a network, using terms such
as router, server, IP address and DNS.
Before the bell
☐ Copy the worksheet, one per student (2 pages).
☐ Ask students to use pencils and keep the passage in front of them.
☐ Keep the answer key on your desk. You do not need to know anything about networks.
☐ Do not allow students to use phones or the school network for this lesson. Everything is on paper.
Say this to start
You use the internet every day, but how does a message get from one device to another? Today you will read a short
passage that explains it in plain words. Then you will work puzzles that show how data is broken into pieces, sent along
different paths, and put back together. You do not need any devices for this lesson.
Run of show
Minutes
What you do
What students do
0–5
Take attendance. Hand out the worksheet.
Look at the title and the word list.
5–15
Tell students to read the passage silently, or ask volunteers
to read paragraphs aloud.
Read the passage and underline the bold
terms.
15–28
Tell students to do Part A (questions 1 through 6), the
vocabulary matching and multiple-choice questions.
Answer from the passage.
28–40
Tell students to do Part B (the packet puzzle and questions
7 through 10). Partners may compare answers on question
7.
Rebuild the message and do the packet
math.
40–47
Tell students to do question 11, which asks them to put the
steps of loading a web page in order, and question 12.
Order the steps and write a short answer.
47–50
Collect all worksheets.
Hand in the paper.
If things go wrong
• If a student asks about a real website, say to stay with the passage and the examples on the worksheet.

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Technology and Computer Science · Computer Science
SP-CS-008 · Free to print and use in your classroom · substituteplans.com
Page 3
• If students ask whether the internet and Wi-Fi are the same, tell them to reread the second paragraph of the
passage.
• If someone says packets are confusing, point to the table: the numbers show the right order.
• If students finish early, use the early finisher list.
Early finishers
• Draw a simple picture on the back of how a message travels from your device through a router and across the
internet to a server.
• Write two sentences that explain the difference between a router and a server.
Support and challenge
• Support: Let students underline in the passage the sentence that answers each question. Have them do
questions 1, 2, 3, 7 and 11.
• Challenge: Ask students to explain why sending a message in many small packets is better than sending it as
one big piece.
Notes for the teacher (you fill this in)
Jot a few lines before you leave. A full Daily Sub Report is in the free Sub Survival Kit at SubstitutePlans.com.
How far the class got / what to pick up next:
Students who were especially helpful:
Anything the teacher should know: