Earth Science — Earth & Human Activity | Unit 2, Lesson 2
📚 Grade: Kindergarten⏱️ Duration: 30–45 minutes🌍 Subject: Earth Science — Earth & Human Activity🧰 Kit Lesson: No
💧 🌊 🧊 ❄️ 🐟
Earth is 71% water — but almost none of it is available for us to drink!
📋 NGSS Standards: K-ESS3-1 — Use a model to represent the relationship between the needs of different plants or animals (including humans) and the places they live. K-ESS3-3 — Communicate solutions that will reduce the impact of humans on the land, water, air, and/or other living things in the local environment.
🎯 Learning Objective
Students will investigate water — Earth's Most Important Resource, make observations during the lesson activity, and explain what they learned using evidence from the lesson.
🎯 The Big Idea
Water is everywhere on Earth — but most of it is saltwater in oceans that living things can't drink! Only a tiny sliver of Earth's water is fresh, drinkable water. That's why we need to use water carefully and not waste it.
71%
of Earth is covered in water — but only 3% is fresh water, and most of that is frozen in glaciers!
Less than 1% of all Earth's water is available for living things to drink. 💧
🔬 The Science
All living things need water to survive — plants, animals, and humans. Water is found in oceans, rivers, lakes, underground aquifers, and even in clouds and soil. Oceans hold about 97% of Earth's water, but it's saltwater — too salty for humans and most land animals to drink. Only about 3% is freshwater. Of that 3%, most is frozen in polar ice caps and glaciers. This means less than 1% of all Earth's water is liquid fresh water available for drinking, farming, and ecosystems.
Because fresh water is so rare and so important, it's a resource we must protect and conserve — even though it might seem like there's plenty when you turn on a tap!
Optional: measuring cup and bowl (for water-saving demonstration)
💧 For the Water-Saving Demo
A bowl of water
Toothbrush
Timer (phone works great)
🔬 Let's Get Started
Step 1 — The Big Question (5 min)
Ask: "Earth is covered in water — 71%! So why do we need to be careful about how much we use?" Let kids guess. Then reveal the secret: most of Earth's water is saltwater! Only a tiny bit is fresh. Draw a simple picture together: a big circle (all of Earth's water), a small slice (freshwater), and a tiny dot (what's actually available to drink).
Step 2 — Morning Water Audit (10 min)
Use the tally sheet to count how many times your family uses water in one morning. Every time someone uses water, make a tally mark!
🥛 Drinking water
🦷 Brushing teeth
🙌 Washing hands
🚽 Flushing the toilet
🚿 Taking a shower or bath
🍳 Cooking breakfast
🌱 Watering plants
Add them up! How many gallons did your family use?
Step 3 — Water-Saving Challenge (10 min)
Test these water-saving habits and feel the difference:
🦷 Tap-off brushing: Brush teeth with the tap running vs. turning it off. Turning it off saves 2–4 gallons per brush — up to 8 gallons a day for a family of two brushers!
🍝 Pasta water rescue: When unsalted pasta water cools, use it to water a houseplant. (Only unsalted — salt water harms plants.)
🚿 Short shower challenge: Time a 4-minute shower vs. a 10-minute one. That's 12 gallons of savings!
Step 4 — Student Worksheet (10 min)
Complete the water tally chart and water-saving pledge on the worksheet. Students circle water-wasting behaviors and draw one way they'll save water.
💬 Discussion Questions
🗣️ Talk about these together:
Earth is 71% water — why do we need to conserve it if there's so much?
Where does your drinking water come from? (Tap → water treatment plant → river or aquifer → rain or snowmelt)
What animals need fresh water? What happens to them if a river dries up?
Can you think of two ways to save water at home starting today?
What does a glacier have to do with your drinking water?
💡 Suggested answer — why conserve if there's so much water?
Even though 71% of Earth is covered in water, almost all of it is saltwater in the oceans — too salty for humans, most land animals, or plants to drink. Only 3% is fresh water, and most of that is frozen in glaciers and ice caps! Less than 1% of all Earth's water is available as liquid fresh water in rivers, lakes, and underground. That tiny amount has to support all of humanity, all land animals, and all plants. So yes — even though Earth looks blue and watery, drinkable water is actually very rare and precious.
🚀 Extensions
🍶 Water model: Use a big bowl (ocean = salt water) and a small cup (fresh water) and a teaspoon (drinkable water) to show the proportions visually.
🌧️ Rain catcher: Set out a cup when it rains. Measure how much falls. Where does rain water go? (Some soaks into soil, some flows to rivers, some evaporates.)
📚 Read aloud:"A Drop Around the World" by Barbara Shaw McKinney or "Water" by Frank Asch
🎯 One-week challenge: Track your family's water use for one week. Can you reduce it by just 10%?
👩🏫 Parent/Teacher Notes
Water audit numbers: The exact gallons don't have to be perfect. The point is to raise awareness that every water use adds up.
For younger children: Focus on the physical activity — tapping off the faucet, timing a shower. The concept of 1% of water being drinkable can be shown concretely with the bowl/cup/teaspoon model.
Worksheet math note: The "Total" column in Part 1 requires multiplying tally counts by gallons per use — this is beyond kindergarten level. Skip the math column; the goal is awareness that each use adds up. Parents can do the multiplication and share the surprising total.
Connection to K-ESS3-1: Emphasize that animals also need fresh water. A fish needs its river. A deer needs a stream. When humans pollute or divert water, animals suffer. This connects habitat needs to human activity.
Connection to K-ESS3-3: Water conservation is a solution to the problem of human impact. Students designing their own water-saving action meets the "communicate solutions" performance expectation.
