1 - Start ~4 mins
You have practised judging whether a source is reliable. Today the question shifts: even before you choose what to open, something else has already chosen what to put in front of you.
You will act as the algorithm, rank a feed yourselves, then watch how the order changes when the feed chases different goals. By the end you should be able to say, in plain terms, what a feed is optimising for and what that choice costs.
2 - Examine and Discuss ~5 mins
An algorithm, in this lesson, is a set of rules a platform uses to decide the order of posts, search results or recommendations. It is not a person reading your feed. It is software ranking items using signals such as how recent a post is, who shared it, how many people liked or watched it, and how long people stayed on similar posts.
The key question today: if the same five posts are waiting, what changes when the feed is told to keep you scrolling, keep you informed, or simply show the newest first?
3 - Hands-on: Be the Algorithm ~14 mins
You are the algorithm. Five posts are waiting for one user. Call out your top two and why, using the signals on each card (who it is from, how people reacted, how old it is, whether it looks useful or emotional).
Then pick a goal (Keep you scrolling, Keep you informed, or Show newest first) and watch the posts snap into the order a real app would use when it chases that goal. Notice which of your top picks stayed up and which sank. Be ready to name one post that moved and what that goal traded away.
Be the algorithm: your feed
4 - Your Turn ~7 mins
Apply the same thinking to a feed you actually use (social, video, music or shopping recommendations). Work on your own, then be ready to share one line with a partner.
- Name the feed and what you think it is mainly chasing: scrolling and watch-time, keeping you informed, newest first, or something else.
- List two signals it seems to use (for example likes, watch-time, friends, purchases, or how new a post is).
- Name one kind of post that probably rises in that feed and one kind that probably sinks, even if the sunk one might be more useful.
- Write one sentence: "When this feed optimises for ___, it trades away ___."
You have four short notes you could read aloud in under thirty seconds. You do not need to open the app if school rules block it; work from memory of how that feed usually behaves.
If time is short, finish the four notes for homework and bring one trade-off sentence to share next time. Protect the make-sense discussion that follows over completing every note in class.
5 - Make Sense ~5 mins
Pull the three goals together.
- Keep you scrolling rewards strong feeling, watch-time and shareability. Useful but quiet posts often sink.
- Keep you informed rewards usefulness and trust signals. Those posts rarely win a pure attention contest.
- Show newest first ignores quality almost entirely. Fresh is not the same as checked.
Feeds, search results and recommendations are ordered for a purpose. Once you can name that purpose, you can ask a sharper question about anything that appears on your screen: why is this here, and what might be missing because of the goal?
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