Site information

Privacy

This edition has no account system, advertising trackers, embedded third-party media or contact form. Site fonts and interface scripts are served from this website. Google Analytics 4 is loaded only after you choose to allow analytics.

Optional Google Analytics

If you allow analytics, Google Analytics 4 receives information about page views, visits, approximate location, browser and device to help us understand how the publication is used. Analytics uses first-party cookies to distinguish browsers and visits. We configure analytics cookies to expire after 90 days; browser settings and renewed activity affect their lifetime. We do not send names, email addresses, worksheet ticks or URL query strings to Analytics. Advertising personalisation and Google signals are disabled in our tag.

Before permission, and after a refusal, our site does not load the Google tag or send analytics requests. The choice is stored in your browser for 180 days. A Global Privacy Control or Do Not Track signal prevents analytics from loading. Use “Analytics preferences” in the footer to change your choice. Refusing analytics leaves all guides and worksheets available.

Google processes analytics information under its own terms. See Google's privacy policy and Google Analytics privacy information. Browser controls can also remove site cookies and stored preferences.

Worksheet interactions

Worksheet ticks exist only in the current page. They are not sent to us or retained in browser storage. Printing uses your browser’s print facility. Do not enter personal or confidential information into printed notes unless your own handling process permits it.

Server requests

The hosting server can process request information such as IP address, requested URL, time, browser information and response status to deliver pages and investigate operational problems. Access is restricted to authorised administration. Server logs are rotated daily when in use. Up to 14 rotated logs are retained in addition to the current log.

External resources

Following an external reference opens another organisation’s website, which has its own privacy practices. We do not control that service.

Edition dated 4 November 2026.