The question to explore

Do I need an umbrella?

How does one piece of information change the next step?

About 9 minutes / Suggested pace / No account needed

  • Workflow
  • Condition
  • Branch
Try the experiment

What this activity helps you do

Try rain, no rain and an unknown forecast. A workflow uses the information it has to choose the next action. Missing information needs its own path.

Local teaching illustration / No AI model call

  1. Start with Unknown. Read why the decision waits.
  2. Choose Rain expected in Forecast. Follow the steps to Take an umbrella.
  3. Choose No rain expected, then Unknown. Explain why missing information should not quietly become no rain.
Unknown forecast: check before deciding whether to take an umbrella.

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The idea

A branch is a choice between next steps. Here, expected rain means take an umbrella; no expected rain means leave it. An unknown forecast means check before deciding.

You choose the forecast and a written rule follows it. No weather service or AI model runs here. A missing forecast does not mean there will be no rain.

Take this with you

What changed?

A workflow connects information, a decision and the next action.

Try explaining it.

If a weather service fails, should the program treat that as a forecast of no rain?

Open a possible explanation

No. An unavailable forecast says nothing about whether rain is expected. Report the missing information and check again before choosing a branch.

Choose what to try next

Keep exploring, or stay here and try another variation.

By Jonathan Simone, with AI assistance. First edition, October 2026. Activities are fictional teaching examples, not measured AI performance. Help us improve this lesson.

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