Science: Beach safety and sand hazards (video-based lesson)

In this 60-minute intermediate-level lesson, we’ll explore the hidden risks of beach activities, focusing on why sand holes can be deadly.

Through listening to an engaging talk, learning key vocabulary like hazard, collapse, and stability, and practicing cause-and-effect grammar, you’ll gain the skills to discuss beach safety confidently.

By the end, you’ll be able to understand important safety ideas and share tips to stay safe at the beach.

Beach safety and sand hazards

Level: Intermediate (B1)
Duration: 60 minutes
Objective: By the end of the lesson, students will be able to understand key ideas from a transcript about beach safety, use related vocabulary in context, and discuss safety precautions using cause-and-effect structures.
Materials:

• Audio or video clip of the transcript, Why Are Beach Holes So Deadly?
• Handouts with vocabulary, comprehension questions, and grammar exercises
• Whiteboard or digital platform for group activities

Warm-up (5-7 minutes)

Objective: Activate prior knowledge and introduce the topic of beach activities and safety.

• Activity: Show a picture of a beach or draw a simple beach scene on the board. Ask:
  • “What do you like to do at the beach?”
  • “Have you ever dug a hole in the sand? Why do people do this?”
• Discussion: Students share ideas in pairs (e.g., swimming, building sandcastles, relaxing). Write key words on the board (e.g., sand, waves, danger).
• Transition: “Today, we’ll listen to a talk about why digging holes at the beach can be dangerous and learn some new words to talk about safety.”

Pre-listening/vocabulary introduction (10 minutes)

Objective: Pre-teach key vocabulary from the transcript to aid comprehension.

• Vocabulary list (selected from transcript)
  1. hazard (n): something dangerous
  2. lifeguard (n): a person who keeps people safe at the beach or pool
  3. collapse (v/n): to fall down suddenly; the act of falling down
  4. geotechnical (adj): related to the study of soil and rock
  5. slope (n): a slanted surface, like a hill
  6. stability (n): the state of being steady or not falling
  7. shear (n/v): a force that causes parts to slide against each other
• Activity
  1. Provide a handout with definitions and example sentences (e.g., “A hazard at the beach is a rip current.”). Students match words to definitions.
  2. Teacher models pronunciation; students repeat.
  3. Quick check: “What’s a hazard you know about at the beach?” or “Who is a lifeguard?”
• Extension: Students make a quick prediction: “Why might digging a hole at the beach be dangerous?”
• Vocabulary for extension
  • Rip current (n): A strong, narrow flow of water moving away from the shore, dangerous for swimmers.
    • Example: “Swimmers should avoid rip currents by staying near the lifeguard.”
  • Embankment (n): A raised structure of soil or rock used to support roads or dams.
    • Example: “The highway was built on a stable embankment.”
  • Surcharge (n): Extra weight or pressure added to a surface, like soil.
    • Example: “People standing on the edge of a hole add a surcharge that can cause a collapse.”
  • Friction (n): The force that resists movement between two surfaces, like soil particles.
    • Example: “Friction between sand particles helps keep a sandcastle stable.”
  • Cohesion (n): The property of soil particles sticking together, especially in clay or wet sand.
    • Example: “Wet sand has cohesion, which makes it easier to shape.”
  • Dilatancy (n): The property of sand expanding when moved, increasing its strength temporarily.
    • Example: “Dilatancy makes beach sand feel firm when you step on it.”
  • Capillary action (n): The ability of water to move upward through small spaces, like in sand.
    • Example: “Capillary action pulls water into the sand, making it stronger.”
  • Shear strength (n): The ability of soil to resist sliding or collapsing under force.
    • Example: “The shear strength of dry sand is lower than wet sand.”
  • Angle of repose (n): The steepest angle at which a pile of soil or sand remains stable.
    • Example: “The angle of repose for dry sand is lower than for wet sand.”
  • Brittle failure (n): A sudden collapse or break without warning, like in sand slopes.
    • Example: “A brittle failure in a sand hole can trap someone quickly.”

Listening (15 minutes)

Objective: Develop listening skills for main ideas and specific details.

• Activity 1: First listening for gist (5 minutes)
  • Play/read the transcript section (0:00–2:34).
  • Question: “What is the main topic of this talk?” (Answer: Dangers of digging holes at the beach and geotechnical engineering.)
  • Students discuss answers in pairs, then share with the class.
• Activity 2: Listening for details (10 minutes)
  • Play/read the transcript again. Provide a handout with 5 comprehension questions:
    1. What is the job of a lifeguard at the beach?
    2. Name two hazards mentioned besides digging holes.
    3. How many people die from sandhole collapses in the US each year?
    4. True/False: More people die from shark attacks than sandhole collapses.
    5. What does geotechnical engineering study?
  • Students answer individually, then check answers in small groups. The teacher reviews the correct answers.

Grammar focus: Cause and effect (10 minutes)

Objective: Practice using cause-and-effect structures (e.g., because, so, if…then) based on the transcript.

• Activity
  • Highlight examples from the transcript:
    • “Because just about every year, the news reports that someone was buried when a hole they dug collapsed on top of them.”
    • “If you know me, you know I would never discourage that act of playing with soil and sand.”
  • Explain structure
    • Because + cause, + effect (e.g., “The hole collapsed because the sand was too wet.”)
    • Effect + so + result (e.g., “The sand was unstable, so the hole collapsed.”)
    • If + condition, + result (e.g., “If you dig too deep, the hole might collapse.”)
  • Practice: Students complete sentences on a handout
    1. The hole collapsed because _____.
    2. Sand can be dangerous, so _____.
    3. If you dig a deep hole, _____.
  • Pair work: Students share their sentences.

Speaking practice (15 minutes)

Objective: Use new vocabulary and grammar to discuss beach safety.

• Activity 1: Pair discussion (7 minutes)
  • In pairs, students discuss:
    • “What are some dangers at the beach?”
    • “What can people do to stay safe when digging holes?”
  • Encourage use of vocabulary (e.g., hazard, collapse, stability) and cause-and-effect phrases.
• Activity 2: Group role-play (8 minutes)
  • Divide students into groups of 3-4. Assign roles: lifeguard, beachgoer, and engineer.
  • Scenario: The beachgoer is digging a deep hole. The lifeguard warns them about dangers, and the engineer explains why it’s risky (using terms like slope, shear, or stability).
  • Groups prepare and perform a short dialogue (1-2 minutes).

Wrap-up and homework (5 minutes)

Objective: Review key points and extend learning.

• Review: Ask: “What’s one new thing you learned about beach safety?” and “What’s one new word you’ll use?”
• Homework:
  • Write a short paragraph (5-7 sentences) about a time you went to the beach. Include at least 3 vocabulary words from the lesson and one cause-and-effect sentence.
  • Optional: Research one other beach hazard (e.g., rip currents) and write 2-3 sentences about it.