Spin to Discover Time

Learning Guide

A simple guide to lead you through the kickoff, the core challenge, and everything in between.

Mai’s Tips

1. Core Connection: The key insight is the direct link: Earth spins, it takes 24 hours to complete one spin, therefore the world is divided into 24 main time zones. If a child grasps this, they have the core concept. Don't let them simply memorize '24 time zones' without the 'why'.
2. Misconception Alert: Children might think time zones are arbitrary lines on a map. The nuance to watch for is ensuring they understand these divisions are a human system designed to align with the natural phenomenon of Earth's rotation and the sun's position, not just random boundaries.
3. Simplify if Stuck: If the 24-hour/24-zone connection is hard, simplify. Ask: 'If it takes 1 hour for our Earth to spin just a little bit, how many 'little bits' would it take to spin all the way around in 24 hours?' Then relate each 'little bit' to a time zone. You can even just mark 4 zones (like quarters) first, then explain how each quarter is divided into 6 more.

Photo by cottonbro studio on Pexels

1Breakfast Time, Everywhere! 5 min

• Start by pointing to a familiar breakfast item, like a bowl of cereal, and ask about the current time. Guide the conversation to imagine friends or family in very distant places. Ask about the time for those people, introducing the idea that it might be different. This stage sparks curiosity.

  • Look at our bowl of cereal. It's breakfast time for us! What time is it right now where we are?
  • Imagine your cousin lives in Australia. If we're eating breakfast, what do you think they might be doing right now? Eating dinner? Sleeping?
  • How can it be morning for us and night for them?

Know Before You Teach

• Good to know: The Earth rotates on its axis, causing different parts of the world to face the sun at different times.
• Because of this, when it's day in one part of the world, it's night in another.
• If they ask: Is time always different in other places? Not always. Places that are close to each other often have the same time. But the further away you go, especially east or west, the more likely the time will be different.
• It's working when: Child shows curiosity about how time can be different (e.g., 'How can that be?').
• If they're stuck: Ask about a specific place they know of, like where a relative lives, and guess if it's day or night there.

• Easier: Focus only on day vs. night for a single far-off location.
• Harder: Ask them to predict if a place to their east or west would be earlier or later in time.

Done when: Child acknowledges that time might be different for people in other parts of the world.

Photo by Steve A Johnson on Pexels

2Spinning Earth, Changing Light 8 min

• Set up a round object (the 'Earth') and a flashlight (the 'Sun'). Have the child hold the flashlight steady while you slowly spin the 'Earth'. Ask them to observe where the light hits. Younger children can point to the 'day' and 'night' sides, while older children can discuss how the amount of light changes as it spins.

  • Hold the flashlight steady, like our Sun. Now, watch what happens to our 'Earth' as I slowly spin it.
  • Where is it bright (day)? Where is it dark (night)?
  • What happens to a spot on our 'Earth' as it spins all the way around? Does it stay light or dark?

Know Before You Teach

• Good to know: The Earth's rotation is what causes the cycle of day and night.
• Only half of the Earth is lit by the sun at any given moment.
• If they ask: Does the sun move? It looks like the sun moves across the sky, but it's actually the Earth that's spinning, making it seem like the sun is moving relative to us.
• If they're stuck: Rotate the object very slowly and pause, asking 'Is this part light or dark now? What about this part?'
• Easier: Focus on observing just one spot on the object and whether it's day or night as it spins.

• Harder: Ask them to describe the path a specific country takes from sunrise to sunset on the model.

Done when: Child observes the creation of day and night on the spinning object and understands that different parts experience light at different times.

Photo by Marina Leonova on Pexels

3Slicing Up the Day 6 min

• Connect the observation of day/night cycles to the Earth's 24-hour rotation. Introduce the term 'time zone' as a way to organize time on a spinning planet. Explain that a time zone is like a slice of the Earth where everyone sets their clocks to the same time. Younger children can point to areas that would have different times, while older children can grasp the mathematical division. End by sharing the France fact.

  • We saw how our 'Earth' spins and changes from light to dark. Did you know the real Earth takes about 24 hours to do one full spin?
  • If it takes 24 hours for Earth to spin, and different places are getting light at different times, how many 'slices' do you think we might divide the world into to keep track of time?
  • We call each of those slices a time zone. It’s like a section of the world where all the clocks show the same hour.

Know Before You Teach

• Good to know: Earth takes approximately 24 hours to complete one full rotation.
• Time zones are sections of the Earth that share the same standard time, typically differing by one hour from neighboring zones.
• If they ask: Are all time zones exactly one hour apart? Most are, yes! But some places, like parts of India or Australia, use half-hour or even quarter-hour differences, usually to better suit their local needs.

• It's working when: Child correctly connects the 24-hour spin to the idea of 24 divisions.
• If they're stuck: Ask: 'If we wanted to make sure everyone knew if it was morning, afternoon, or night, and it takes 24 hours to go around, how many different 'labels' for time would we need?'
• Easier: Focus on the idea that because the Earth spins, we need different 'time labels' for different places.
• Harder: Discuss why some countries might choose not to follow exact hour lines for their time zones (e.g., to keep a whole country on one time).

Done when: Child can describe what a time zone is in simple terms and connect it to Earth's 24-hour rotation.

Photo by cottonbro studio on Pexels

4Making Our Time Zone Model 9 min

• Have the child mark 24 lines (like meridians) on the round object using a marker. Encourage them to try and make the slices as even as possible. Discuss how these lines are imaginary boundaries. Younger children can help draw any lines, while older children can try to divide the object into 24 roughly equal sections.

  • We're going to draw our time zones! Remember how many hours it takes Earth to spin? Let's draw that many lines on our 'Earth'.
  • Can you draw 24 lines, like slices, from the top to the bottom of our orange?
  • Now our 'Earth' has 24 time zone slices!

Know Before You Teach

• Good to know: There are 24 major time zones, each roughly 15 degrees of longitude wide (360 degrees / 24 hours = 15 degrees/hour).
• Time zones are generally based on longitudinal lines but are often adjusted to follow political boundaries for convenience.
• If they ask: Are these lines real? No, these lines are imaginary, like the lines we draw on maps. They help us understand and organize things, but you wouldn't see them if you flew over the Earth.
• It's working when: Child attempts to make the divisions somewhat even and counts them.
• If they're stuck: Help by drawing the first few lines and then encouraging them to continue the pattern.

• Easier: Focus on drawing any lines to divide the ball, rather than exactly 24 or perfectly even.
• Harder: Ask them to try and estimate where the lines should go if they were 15 degrees apart, or relate it to cardinal directions (north/south poles).

Done when: The round object is marked with approximately 24 divisions representing time zones.

Photo by Karina Badura on Pexels

5Why 24? 2 min

• Conclude by asking reflection questions that reinforce the core concept. Guide them to connect Earth's 24-hour rotation directly to the existence of 24 time zones. Younger children can recall the spinning ball and light; older children can explain the full cause-and-effect relationship.

  • We started wondering why time is different in other places. What did we discover about the Earth that helps explain that?
  • How does Earth's 24-hour spin help us understand why there are 24 time zones?
  • What's the most interesting thing you learned about time zones today?

Know Before You Teach

• Good to know: The universal system of time zones helps standardize time across the globe, essential for communication, travel, and commerce.
• The Prime Meridian (0 degrees longitude) in Greenwich, England, is the starting point for measuring time zones (Greenwich Mean Time - GMT, now often UTC).
• If they ask: Do all countries use time zones? Almost all do! But very large countries sometimes have many time zones, like Russia or the USA. China, however, uses only one time zone for the whole country, even though it's very wide!
• Easier: Prompt them to just remember one big idea, like 'Earth spins, so time is different.'

• Harder: Ask them what would happen if we didn't have time zones, or why it's important for everyone to agree on how time works.

Done when: Child can articulate the relationship between Earth's spin, 24 hours, and 24 time zones.

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