What we are making: a plan on one page, and a place to put the thing.

The brief

Build a networked device that measures something real, in a real place, and shows it on a page somebody else can use. It stays where you put it for at least a week. It is judged on whether a stranger can walk up, look at the page, and understand it.

Three that have worked

1. The library is too warm. Temperature on a page, red above a number the librarian chose.
2. Is the lab free? A light sensor and a page that says OCCUPIED or FREE.
3. How loud is the corridor at break? Sound level, with the loudest of the day.

Write down five things

1. The sentence. What it measures, in what units, and what it tells somebody.
2. The person. Who reads the page. By name or by role.
3. The place. Where it goes, and — this matters — whether there is a power socket there and whether the WiFi reaches.
4. The number. Your threshold, and how you will choose it.
5. What it cannot do. Write this now, honestly, not in May.

Before you leave

• Your five answers, signed off.
• Permission from whoever owns the place you chose.
• Your parts checked out.