All lessons › Challenge: Moon, tides and eclipses › Lesson 3
Australian primary science · Years 5–6 (challenge) · Lesson 3 of 3
The tide timetable puzzle
Inquiry question: Why are high tides about 50 minutes later every day, and bigger at some times of the month?
Marked no materials needed
Pattern seeking
What students learn
Tides are caused mainly by the Moon’s gravity pulling on Earth’s oceans. Because the Moon moves along its orbit, Earth has to spin about 50 minutes extra each day to catch up, so tides come later. When the Sun and Moon line up (new and full moon), tides are biggest.
Success criteria
- I can describe the patterns in a tide table.
- I can explain why tides come about 50 minutes later each day.
- I can link the biggest tides to the moon phase.
Preparation and materials
Before this lesson: Students know the Moon orbits Earth in about a month and Earth spins once a day (lessons 1 and 2).
- iPads with Bottlebrush Education open (nothing else needed) — 13 (one per pair)
- Projector or big screen — 1
Teacher setup
- Open Earth & space › Play › Space and rock clues on your screen to demonstrate.
- Check the iPads are charged and set to Your year › Years 5–6.
Safety and adaptations
Follow school science and equipment risk assessment procedures for the materials used.
Review your school policies and curriculum requirements before teaching.
How to investigate
The lesson sequence should leave pupils with evidence to interpret, not only an activity to finish.
- Pairs find the pattern in the high tide times and work out the daily delay.
- Use the pattern to predict the morning high tide time for the next Saturday (7 days later).
- Find the pattern in the heights table and link it to the moon phase.
- Draw Sun, Earth and Moon at spring tide and at neap tide.
- Answer the fishing puzzle with evidence.
Teacher modelling prompt
Show the tide table. Think aloud: “Saturday’s first high tide was 6:10 am. Sunday’s was 7:00 am. That’s 50 minutes later. Monday, 7:50 am: 50 minutes again. So there’s a pattern. Next, the heights: they’re biggest on the full moon day. I wonder why?” Draw Earth with an ocean bulge towards the Moon and ask: if Earth spins once in 24 hours but the Moon has moved a little, how long until we face the Moon again?
Record and explain evidence
Recording question: Why are high tides about 50 minutes later every day, and bigger at some times of the month?
| Day | Morning high tide time | Minutes later than the day before | Tide height | Moon phase |
|---|---|---|---|---|
| ________________ | ________________ | ________________ | ________________ | ________________ |
Example recording headings; record actual observations, including inconclusive results.
Discussion prompt
Use the pattern to check who is right.
Provided example or reference data
Example tide data for an east-coast beach (rounded, in the style of a Bureau of Meteorology tide table)
| Day | Moon phase | Morning high tide | Evening high tide | Highest tide height |
|---|---|---|---|---|
| Saturday | Full moon | 6:10 am | 6:35 pm | 1.9 m |
| Sunday | 7:00 am | 7:25 pm | 1.9 m | |
| Monday | 7:50 am | 8:15 pm | 1.8 m | |
| Tuesday | 8:40 am | 9:05 pm | 1.7 m | |
| Next Saturday (about 7 days later) | Last quarter | ? | ? | 1.4 m |
| About 14 days later | New moon | about 5:45 am | about 6:10 pm | 1.9 m |
Check the data source in the teacher lesson. Illustrative or fictional data are not measurements collected by your class.
Check understanding
What should pupils know? What causes tides?
Explain with evidence: Explain why high tide is about 50 minutes later each day.
Apply the idea: A boat ramp can only be used when the tide is high. Would it be easier to use around full moon or quarter moon? Why?
Teacher answer guidance and saved classroom work are available through the main lesson experience where supported.