Greenwich Mean Time Assembly Presentation

A school assembly on Greenwich Mean Time.

This PowerPoint gives teachers a clear, engaging overview of Greenwich Mean Time (GMT), explaining how the Prime Meridian at Greenwich became the world’s central reference point for timekeeping. It covers the historical decisions that made GMT the global standard, the problems caused by differing local times before its adoption, and the scientific reason why GMT is based on “mean” solar time. The presentation also introduces time zones, showing how all global time is measured relative to GMT, and explains British Summer Time (BST), why it was created, and how the clock changes affect daily life. It concludes with fun facts and reminders of GMT’s continuing importance for navigation, communication, and international coordination.

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