Lesson 12: Sources and Search Engines


This lesson encourages students to think more critically about how web searches work and how to find relevant and trustworthy information online. After viewing and discussion a video about how search engines work, students will search for information about several unlikely animals. They'll need to analyze the sites they find for reliability in order to identify which of the animals is actually a hoax.


Students use search engines all the time. They take for granted how hard it is to produce search engine results in seconds. In order to give them a deeper understanding of the algorithms that control modern search, students will develop their own algorithms.

This lesson connects back to Unit 1, which is explicitly called out in the Wrap Up. This a problem that humans and computers solve differently. In fact it's a problem that computers solve better than humans, as a human would take too much time to search through huge amounts of data. Humans, however, still have a major role to play in searching effectively, as computers are unable to reliably tell us which websites contain trustworthy information and which are scams. Through this lesson, students will collaboratively create a class checklist that they can use to vet websites they come across for relevance and trustworthiness.


Warm Up (10 minutes)

Activity (30 minutes)

Wrap Up (5 minutes)


Students will be able to:

  • Use basic web searching techniques to find relevant information online
  • Identify elements that contribute to a website's trustworthiness or untrustworthiness



Heads Up! Please make a copy of any documents you plan to share with students.

For the Teacher

For the Students


  • Algorithm - A precise sequence of instructions for processes that can be executed by a computer
  • Relevant - Closely connected or appropriate to the matter at hand
  • Search Engine - A program that searches for and identifies items in a database that correspond to keywords or characters specified by the user, used especially for finding particular sites on the World Wide Web.
  • Trustworthy - Able to be relied on as honest or truthful

Teaching Guide

Warm Up (10 minutes)

Internet Scavenger Hunt

Group: Place students in pairs.

Distribute: Each group will need a copy of Internet Scavenger Hunt - Activity Guide

Transition: Send students to the computers to prepare for the scavenger hunt.

Goal: The first three prompt questions are intended to help students identify any searching techniques that they currently use. If students don't have clear strategies, you may want to spend some time discussion basic search techniques. Keep track of search strategies on the board for reference later.

The last question gets to the focus of the activities in this lesson. It's likely that students didn't consider whether or not their information was accurate, but if they do come up with some ideas, make sure that you track them in a place where they can be referred to later in the lesson.


When I start the clock you will have exactly 7 minutes to complete as much of this scavenger hunt as you can. Your goal isn't to answer every question on this list, but to find as much accurate information as possible in the time you've been given.


  • Which things were hardest to find?
  • Which were easiest to find?
  • What strategies did you use to find things online?
  • How did you know the information you found was correct?

Discuss: Student pairs share out what they were able to discover about the scavenger hunt and what strategies worked well for finding information.

Activity (30 minutes)

Relevant and Trustworthy Sites

Display: Watch the How Search Works - Video with the class.


Now that we know a little bit more about how search engines work, we're going to search for some information about some of the world's strangest animals.

Group: Place students in pairs.

Distribute: Give each pair one copy of Strange Yet True Animals - Activity Guide

Unlikely Animals

Teaching Tip

Students may come upon sites that explain that the pacific northwest tree octopus is in fact a fictional animal. If so, you can ask them to think about why they believe some sites over others, and how they are sure that the other two animals are real. Have them continue filling out the worksheet with these questions in mind, and let them know that they will be able to share their thoughts later in the activity.

You can find more untrustworthy websites in this forum post.

Search: Give student pairs some time to search online and fill in the table on the activity guide. They should have little difficulty finding this information by just searching for the names of each animal.

Share: Ask student pairs to share out their answers for each of animals. If, during any point in the share out, others in the class disagree with an answer encourage them to discuss where and how they found their information.

Vocab: It's likely that students found websites that were relevant to their topics, but how do we know if they are trustworthy?


You did a great job finding websites that were relevant to your search. You found a lot of interesting information about those strange animals, but is any of it real? You and your partner have five minutes to decide which of these animals are real, and which are made up. For each of your decisions you'll need some supporting evidence that shows why your source websites are either trustworthy, or untrustworthy.

Teaching Tip

Just in Case: The Pacific Northwest Tree Octopus is the fake animal.

Search: Give students five more minutes to look through their source sites to try to figure out whether or not they're trustworthy.

Share: Allow each pair to share out their assessment of trustworthy and untrustworthy sites. Push students to give detailed reasons for why they trust a site or not, and keep track of them on the board. Once all of the pairs have had a chance to share, reveal the that the Tree Octopus was the only fake animal. Depending on how accurate your students were, consider visiting the site as a class to explore some of the clues that it's not quite right.

The Trustworthiness Checklist

Teaching Tip

Prompting Conversation: If your students are struggling to come up with ideas, consider prompting them with any of the following:

  • What does the web address of a trustworthy or untrustworthy site look like?
  • Is a well designed site more likely to be trustworthy, or untrustworthy?
  • Would you expect a trustworthy site to have easily found contact information?
  • Can you learn anything from the kinds of ads that a site displays?

Set Up: Start a poster on the wall labeled Trustworthiness Checklist.

Group: Place students in groups of 4-5.

Prompt: Now that we've identified some sites that are, and are not, trustworthy, work with your group to come up with a list of things to check for when trying to determine whether or not to believe a website.

Share: Have groups share out their lists. As a class, generate a class Trustworthiness Checklist on a poster. You can refer back to this in the future whenever asking students to find information online.

Discuss: Think about your own websites - do you think people would find your site trustworthy or untrustworthy? What changes could you make to your site to encourage users to trust your content?

Wrap Up (5 minutes)

Human versus Computer Searching

Journal: In Unit 1, we looked at the differences between how computers solve problems and how humans solve problems. What are the differences between the way search engines work and how humans search for resources?

View on Code Studio


After first completing a web search scavenger hunt, students will learn about the inner workings of search engines and have an opportunity to flex their analytical skills in a search for strange and unlikely animals.


  • Algorithm - A precise sequence of instructions for processes that can be executed by a computer
  • Relevant - closely connected or appropriate to the matter at hand.
  • Search Engine - A program that searches for and identifies items in a database that correspond to keywords or characters specified by the user, used especially for finding particular sites on the World Wide Web.
  • Trustworthy - able to be relied on as honest or truthful.


Standards Alignment

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CSTA K-12 Computer Science Standards

IC - Impacts of Computing
  • 2-IC-20 - Compare tradeoffs associated with computing technologies that affect people's everyday activities and career options.
  • 2-IC-21 - Discuss issues of bias and accessibility in the design of existing technologies.
  • 2-IC-23 - Describe tradeoffs between allowing information to be public and keeping information private and secure.