Smell This!

What You Need:

• photograph of a dog known for its excellent sense of smell, such as a bloodhound or German shepherd
• 3 small opaque containers
• lemon juice
• baking soda
• vinegar
• vanilla
• blindfold
• knife
• cutting board or plate
• 5 different foods* cut into a small cube shape (approx 1 cm.), such as: cheese, apple, potato, cantaloupe, pear, watermelon, cucumber, carrot, onion
• cups of water for each child. Note: Make sure your child is not allergic to any of the foods used in this experiment.

What to Do:

1. PREPARATION: Inside each of the 3 mystery containers, put one of the following substances: lemon juice, vinegar, and vanilla. Cut the fruits, vegetables and cheese into uniform cubes about 1 cm. by 1 cm., organizing each food into one of three piles — in a particular order (so that one is clearly first, second, and so on.)
2. Ask your child if some animals smell things that people cannot? Your child may talk about how animals such as dogs, bears, and sharks have much stronger senses of smell than we do, and can identify scents we cannot. Have your child discuss how animals, such as wolves, use their strong sense of smell to survive in the wild. Help your child understand that a strong sense of smell can help an animal to catch its prey (animals it wants to eat), and to escape from predators (animals that want to eat it).
3. Let your child watch "Play Date with Annie," (above) in which Buddy the T. rex demonstrates his powerful sense of smell.
4. Have your child close his eyes and smell each of the 3 mystery containers, one at a time and say what he thinks the scent is. (You might encourage him to use Buddy’s favorite word "hypothesis" when giving their answer. Example… "My hypothesis is that this first container has lemon juice!")
5. Ask: "Do you think your sense of smell is connected to your sense of taste?" To explore the answer, he is going to do an experiment. Put a blindfold on your child (or have him close his eyes), and have him hold his nose. Explain that you are going to put a small piece of food in his mouth that is in a cube shape. His job is to see if they can figure out what the food is—without being able to smell it. Have your child take a sip of water between each example, to clean out his mouth. Give a sample of each cubed food and ask your child to make a prediction. You might give a clue that the food is a fruit, or vegetable. You can also allow your child to spit out the food sample if they wish. Ask him to say aloud what food they think is in his mouth. Do not reveal the answers yet.
6. Repeat the process in Step 5, presenting the three cubed foods in the same order — but this time let your child use their sense of smell (not holding their noses). Again, ask your child to make his prediction of what the foods are — but do not reveal the answers.
7. Have your child remove his blindfold (or open his eyes) to reveal the answers. Discuss how our sense of smell affects our ability to taste different foods.

Extensions:

• Have your child think of as many different smells as he can. He might consider things like "cookie baking in the oven," "an old garbage can" and so on. As she suggests ideas, write them down in three lists: LIKE IT, DISLIKE IT, NO STRONG FEELINGS. Ask your child to talk about how different smells can affect their moods.
• To help your child explore the connection between the sense of sight and the sense of taste, have him taste five different jelly beans with their eyes closed and see if he can tell the flavors. Older children might be interested in exploring at the library or on the Internet how candy companies that make jelly beans use chemicals to artificially create tastes of different foods.