Tsunamis
Know what a tsunami is: a very large, fast ocean wave caused by an earthquake or volcanic eruption under the sea, which can cause great damage when it reaches land
Lesson
Set out your lesson
“A tsunami is a series of waves caused by a large, sudden displacement of water. Many start with undersea earthquakes; landslides and volcanic activity can also cause them. Not every undersea earthquake does. In deep water a tsunami can be low and very fast; near shore its height and currents can become dangerous. Safety: Use only a fictional coast. This is not emergency advice; real warnings require official local guidance and adult support. Stop: Stop at the paper explanation. No water-wave experiment, coast visit, evacuation rehearsal, or real warning interpretation.”
Bring to the table
- Paper
- Pencil
- Long paper strip
Extra for the adult
Worked example. Model card A → B. Answer: displacement starts waves that travel away; a tsunami is not simply normal wind surf made taller. The town could flood because wave water and strong currents reach land, but this drawing cannot give arrival time or flood depth.
Optional challenge. Explain why a low wave offshore can still be dangerous near a coast without using this sketch to predict a real event.
What to notice. Keep the sequence and strip. Note help with ordering, reading, or distinguishing normal surf from tsunami waves.
Share and support
Family records and proof options
Keep a record of your learning
Save photos, notes, and attendance. Export a proof packet for compliance or portfolio reviews.
Learning resources
Extra practice links — they do not replace Gakuva’s teaching approach.
USGS · Practice link — not the full lesson
Earthquake Hazards Program
Before you open · source notes
Earthquake Hazards Program supports Tsunamis. An adult previews and guides; this is a learning page, not a scored quiz.
Free educational page, no sign-in required for the tested path.
Before you openAsk the learner one fact they learned and one question they still have.
Opening this link does not save learning or assess mastery.
Source, access and review notes
Public USGS page. An anonymous GET on 2026-11-12 returned HTTP 200 with no login or payment prompt for this URL. Opening the link does not save practice or assess mastery. An adult should preview and guide the learner.
USGS. “Earthquake Hazards Program.” External page; Gakuva does not copy, host, embed, or redistribute materials.
Unknown — link only
Check understanding
- Explain that a tsunami is caused by an earthquake or eruption under the sea
- State that tsunamis travel very fast across the ocean
- Describe the damage a tsunami can cause when it reaches the coast
“If your child hears the word 'tsunami' on the news, can they explain that it's a huge wave caused by an earthquake or eruption under the ocean, and that it can travel very fast across the sea?”
Curriculum record
- Type
- Conceptual
- Subject
- Science
- Domain
- Volcanoes & Earthquakes
- Age range
- Ages 7–9