Healthy kids quest: Water for me, please!

Feeling thirsty? Why not have a big glass of cold water? Water is free and it’s essential to our survival. When we make water our main drink of choice, we satisfy our thirst and feel good. But water alone is not the only way to stay hydrated: many different beverages and foods contain a percentage of water, and they can be tasty and just as refreshing!

Curriculum links

• Health and physical education: Healthy living
• Science and technology: Life systems
• Science and technology: Earth and space systems

Learning objectives

• Understand that we need water to survive
• Discover why our bodies lose water and how to rehydrate
• Realize that water is also found in other drinks and foods

Learning methods

• Estimating the quantity of water on the Earth
• Estimating the quantity of water in the human body
• Estimating how much water a human being needs

Materials

• Copies of the ‘Water for me, please!’ activity sheet (please see the printable PDF at the bottom of the page)
• Blue crayons or pens (1 per student)
• Supplies for 4 water estimating stations

Pre-activity: Set up water estimating stations

Before beginning the activity, assemble the supplies needed and set up the four water estimating stations on tables or desks. Position the stations around the classroom. Use transparent, disposable plastic glasses (250 ml size).

Station 1

• Globe (Earth)
• 4 glasses:
  • 1 empty glass
  • 1 glass of water, one-quarter full and labelled 25%
  • 1 glass of water, one-half full and labelled 50%
  • 1 glass of water, three-quarters full and labelled 75%
• A piece of cardboard indicating the number of the station, its name and the question for students to consider at this station:
  • Station 1: Water on Earth
  • Question: How much water is there on the Earth?

Station 2

• 4 glasses:
  • 1 empty glass
  • 1 glass of water, one-half full and labelled 50%
  • 1 glass of water, two-thirds full and labelled 65%
  • 1 glass of water, three-quarters full and labelled 75%
• A piece of cardboard indicating the number of the station, its name and the question for students to consider at this station:
  • Station 2: Water in my body
  • Question: How much water is there in my body?

Station 3

• A piece of cardboard indicating the number of the station, its name and the question for students to consider at this station:
  • Station 3: Time to take a sip!
  • Question: When should I drink water?

Station 4

• Pictures of the following items:
  • Green coconut
  • Watermelon
  • Raisins
  • Smoothie
  • Cashews
  • Meat jerky
  • Cup of milk
  • Cucumber
  • Bowl of soup/broth
  • Dried pasta
• A piece of cardboard indicating the number of the station, its name and the question for students to consider at this station:
  • Station 4: Water is everywhere!
  • Question: Which of these food items contain water?

Instructions

Introduction

1. On the board, write the words: water, food, and oxygen. Read the words out loud and ask students to identify which of these three elements is the most important for the human body. Carry out a survey. Read each of the words out loud, asking students to vote for each one by raising their hands.
2. Explain that all three of these elements are vital for humans: we need them all at the same time to survive and to feel good.
   • Oxygen is the most important element. We can survive for only a few minutes without oxygen.
   • Water is the second most important element. We can survive for only a few days without water. Because we lose water every day through normal activities, it’s important to keep replacing it.
   • Food is the third most important element. We can survive for only a few weeks without food.

Water estimating stations

1. Explain to students that through this activity they will find out why water is important and how to get enough water every day. To do this, they will visit four water stations.
2. Give each student a copy of the Water for me, please! activity sheet and tell them they are responsible for recording their answers in the appropriate spaces. Divide the class into four groups.
3. Before beginning the activity, explain what they will be doing at each station.

Station 2: Water in my body

Question: How much water is there in my body?

Explain that each glass represents a child’s body. Students must choose the glass they think represents the proportion or amount of water in their bodies. For example, a student who thinks that half the human body is made up of water would choose the half-full glass. They should record their estimates on the activity sheet and colour in blue the part of the human body they think is made up of water.

Answer: The amount of water in the human body varies depending on a person’s age.

At birth, our bodies contain a lot of water: 75% of a baby’s body is made up of water.

Show the glass of water that is three-quarters full. As people get older, their bodies contain less water. Only 50% of an elderly person’s body is made up of water. Indicate the glass one half full of water. Finally, show the glass that is two-thirds full of water. Explain to students that approximately 65% of the body of someone their age is made up of water. This is because a young person’s body still contains a lot of water. The goal of drinking water is to stay hydrated. What does “hydrated” mean? If we are hydrated it means we have enough water in our bodies. To be dehydrated means to not have enough water.

• Water is essential to all animal and plant life
• We need water to survive because our bodies are made up mostly of water
• Our bodies need water to function
• Our blood consists mostly of water
• Water is transparent. It has no odour or taste.
• Ask students to share their estimates. How many of them guessed correctly?

Station 3: Time to take a sip!

Question: When should I drink water?

Ask students to reflect on and brainstorm about when it is that they feel thirsty and need to take a drink. What is the weather like? What activities are they doing? Ask them to write their answers on the activity sheet.

Answer: The amount of water we need to take in every day depends on our age, the weather, our activity level, and our health.

• We lose water every day through sweating and breathing, and when we go to the washroom. We need to replace this water every day by eating and drinking.
• We need to drink more water when we are active or hot.
  • Our bodies control their temperature by releasing water in the form of perspiration, or sweat. As sweat evaporates, our bodies cool down and our body temperature drops. We need to replace the water lost through sweating.
  • We need to drink water before, during, and after taking part in moderate or vigorous physical activity.
• We particularly need to drink more water when we are physically active for a long time, for example, during a soccer tournament
• Instead of waiting till we’re thirsty and then gulping down larger amounts of water, it’s better to sip water throughout the day, even when we don’t feel thirsty. We will stay hydrated and our bodies will do a better job of retaining the water. We also need to drink more water when the weather is very hot and humid or dry.
• Feeling thirsty is one way that our bodies tell us we need more water. You may have heard that we need to drink 8 cups of water every day, but, while we all need to drink water every day, each person needs a different amount. Some people need 8 cups, some need more, and others need less. What’s important is that we listen to our bodies and drink when we are thirsty.
• When we’re sick, it’s especially important to sip on water. Food and drink such as chicken noodle soup and hot tea contain a lot of water. These may be easier and tastier to take in when we’re sick and don’t have much of an appetite.
• The signs of dehydration are:
  • A feeling of thirst
  • Tiredness
  • A headache
  • A lack of concentration
• Ask students to share their estimates. How many of them guessed correctly?

Plants need four elements to survive: sunlight, soil, air, and water. In this experiment, students observe the effects of water on plants.

Curriculum link

• Science and technology: Life systems

Learning objectives

• Learn about the effects of water on plant growth and development
• Understand that water is vital to plant life
• Realize that plants, just like humans, need water to survive and stay healthy

Learning methods

• Performing an experiment to compare the growth and development of three groups of plants receiving different quantities of water
• Establishing and verifying hypotheses
• Compiling and analyzing data

Materials

• 3 plants
• Labels and markers
• Watering cans
• Measuring cups
• Copies of the ‘Drought or drowning’ activity sheets (1 set for each student)

Pre-activity: Set up water estimating stations

1. Take three plants of the same type and age. Bean plants that have been germinated in a pot on the windowsill can be used. Make sure that the plants are approximately the same size.
2. Label the first plant as ‘plant A’. Students will water this plant every day.
3. Label the second plant as ‘plant B’. Students will water this plant every Monday and Thursday.
4. Label the third plant as ‘plant C’. Students will never water this plant.