Make Water Safe to Drink
Lesson preview: the Mini Lesson and Vocabulary are open to everyone. Guided practice, exercises, the parent checklist and the printable PDF worksheet come with full access (free 7-day trial or membership).
What you will learn
- 1Explain why unsafe water is dangerous and must be treated
- 2Make water safe using the two steps — filter, then purify
- 3Describe wild ways to purify water without modern gear
- 4Explain why sea water must be distilled before drinking
Mini Lesson
Your body can last about three weeks without food — but only about three days without water. So finding water is not enough: you have to make it SAFE. Dirty, contaminated water carries germs too small to see, like bacteria and tiny parasites, and they can make you very sick. The good news: if you know how, you can turn almost any water into safe water. It takes two jobs — first take the dirt out (filter), then kill the germs (purify).
🌿 The Wild Way (with only what nature gives you)
- FIND it with your grown-up: rain, a running stream, or dew wiped off the grass at dawn. Moving water beats still water.
- FILTER it: pour it through layers of grass, sand, and charcoal from an old, cold fire, then gravel. The charcoal grabs the dirt and the bad taste.
- PURIFY it — you still must kill the germs. ROCK-BOIL: a grown-up heats dry stones (never wet river rocks, which can crack) in the fire, then drops them into a wooden or bark bowl of water until it boils hard (a rolling boil).
- No fire? Build a SOLAR STILL: dig a hole, put a cup in the middle, cover it with a sheet of clear plastic, and weigh the center down with a pebble. The sun lifts clean water as vapor and it drips into your cup — leaving the dirt and even salt behind.
Never drink water just because it LOOKS clean — the germs are invisible. And remember: filtering takes out the dirt but NOT the germs, so you must always purify too. Never drink sea water straight — the salt makes you thirstier and sicker. And never eat snow to get water; a grown-up melts and purifies it first - eating it steals your body heat. A grown-up does all the boiling and handles any fire.
Words to know
contaminated
Water that has germs, dirt, or poison in it that can make you sick.
filter
To pass water through layers like sand and charcoal to take the dirt out.
purify
To kill the invisible germs in water, usually by boiling it.
sediment
The mud, sand, and bits that float or sink in dirty water.
solar still
A covered hole that uses the sun to lift clean water and leave dirt and salt behind.
distill
To turn water to steam and catch it clean again — the way to make sea water drinkable.
🧠 Survivor’s Trick: no cup and no fire? With your grown-up, tie a clear plastic bag over a leafy green branch they have named safe, in the sun. The leaves “sweat” and water collects in the low corner of the bag — and your grown-up decides if it is safe to drink.
Unlock the full HSEA system for 7 days.
Add your first kid profile and your 7 days start: every lesson in every grade, saved progress for each child. Nothing to set up, no card required, nothing to cancel.
- ✓ All 1,880 lessons, Grades 1–6, every subject
- ✓ Profiles + saved progress for every kid
- ✓ Printable lessons with answer key