Theme - Developing Positive Attitudes to New Foods - Investigating Foods Through a Scientific Approach. Ages/Grade Level: 4-5. Subject Area: Science

Transcription

1 The Whole Carrot Contest: Learning the Scientific Method Through A Comparative Taste Test and Data Collection Activity Lesson By Service Member Daniel Marbury, Michigan Theme - Developing Positive Attitudes to New Foods - Investigating Foods Through a Scientific Approach Ages/Grade Level: 4-5 Subject Area: Science Summary: This lesson will introduce and engage students in all of the steps of the scientific method as they experience a healthy food. The first part of the activity engages students in trying two carrots that differ slightly, using words related to color, taste, texture, smell, etc. to describe them. This sampling gives students the opportunity to practice observing and describing foods with new vocabulary and through a scientific mode of observation. The second half of the lesson is a data collection, organization, and graphing exercise. Students vote on their favorite sample variety, then the class as a whole collects this data in order to generate a tally chart and bar graph depicting the class preference. Goals: Students will try healthy foods to practice identifying and distinguishing different aspects of their experience of food, including flavor, temperature, texture, smell, color, etc. Students will expand their vocabulary of new descriptive adjectives. Students will use adjectives to describe their observations about foods. Students will learn about the cultivation and nutrition of local and seasonal fruits and vegetables. Students will practice communicating their observations to others in pairs or small groups. Students will practice listening closely to their classmates. Students will learn the importance of being respectful of their classmates differences. Students will learn the steps of the scientific method. Students will learn how to conduct a blind taste test. Students will learn how to collect and organize data from an opinions survey. Students will learn how to generate and display a tally chart and bar graph using data collected among peers. Students will learn to identify and describe the parts of a bar graph. Students will learn how to interpret the meaning of a tally chart or bar graph. Materials: Selection of two different kinds of carrots. (Example: one bag of baby carrots from a grocery store and one bunch of whole, farm-fresh carrots) Knives, cutting board, napkins, small serving plates Poster or white board for writing words and charts

2 Word bank for each student or group of desks Graphing paper Ruler Pencils, pens Preparation: Prep Time: 45 min 1. Make copies of graph paper and tasting chart for each student. 2. Cut up each type of carrot into small, one bite sample pieces. Keep samples separate and refrigerate until just before class. 3. Place on a few serving plates to easily pass out to students. Label plates A and B for different samples. Teaching Time: 45 Minutes Opening: 1. Discuss the difference between fact and opinion (objective vs. subjective), including the difference in the way that we establish each. As a class make a chart of words falling in the two different categories. Discuss the importance of fact-based research in a scientific experiment. 2. Explain that for the upcoming activity we will be trying foods in the context of a scientific experiment. Establish guidelines for tasting food in your class which may include: The No Thank You bite rule Everyone must take at least one small taste before saying No Thank You. Don t Yuck My Yum It can ruin an eating experience for you when another person says negative things about your food. Reinforce the idea of using descriptive fact words, not opinion words such as good, bad, eww, or gross. 3. Discuss the 5 senses in tasting, referencing them on the student Tasting Chart. Lesson Procedure Part 1: Comparative Tasting & Objective Observation (15 min): 1. Present two different kinds of carrot samples, but do not disclose which sample is which. Explain to students that one food came from a local farm while another traveled from another state or country to arrive in your class. 2. Introduce or review the steps of the scientific method. Ask students, How do you think the scientific method could be incorporated into an activity involving food? Guide the class to the experimental question, Will students in our class prefer carrots from a local farm? 3. Explain to students that they will be forming a hypothesis for the results of a taste test in which they will test the two samples for popularity with students from the entire class/school. One hypothesis example is: If we purchase carrots from a local farm, then they will be more popular with students in our class OR If we buy carrots from a local farm and from a grocery store, then our class will not notice a difference. 4. Describe that they are about to use all of their senses to make observations about the color, smell, texture and taste of the carrots. Instruct students to have a pencil and paper ready to record their observations and explain the observation procedure. 5. Pass out Sample A to each student and try together as a class. As the food is being passed out, use this time to describe fun gardening or nutritional facts about the fruit or vegetable. 6. Silently record observations for 2-3 minutes, then share as a group for 5-6 minutes. Ask students to volunteer adjectives they wrote down to describe the sample. 7. Repeat Step 6 for Sample B. 8. Record new adjectives as a class in a word bank on the board or on a poster. Keep this word bank somewhere visible in the classroom. 2

3 Part 2: Graphing to Analyze Results (20 min): After the comparative tasting activity, ask students to vote for their preferred sample. Count the votes for each sample. Once you have finished collecting votes for your two samples, you are ready to organize and analyze data. Step 1. Organize Data Distribute graphing paper to the class. Instruct students to count the number of boxes in the grid both horizontally and vertically on the page. On your class writing board, record the number of rows and columns on the graph paper grid for later reference. Ask students to flip over their graphing paper to the opposite side and preface that you are about to create a tally sheet of your votes. On your class writing board make a grid with three rows and two columns. Identify the first row as the place for labels to describe the information below and guide them in determining the proper labels. Foods Tasted Votes Number Food 1 Food 2 Select two pairs of students for the task of counting the votes and ask them to count together aloud in order to check one another. Instruct the rest of the class to make one tally mark each time they count and be sure to explain diagonal tallies each 5 th number or multiple of five. When the students have finished counting votes, instruct the class to write the numeral describing the total quantity of votes in the third column. Step 2: Graph Results You may use the following acronym to introduce all the parts of the graph: T.A.I.L.S. for Title, Axes, Interval, Labels, and Scale Ask students to return to the graphing side of their paper. You may give students the option of turning their paper to landscape or portrait orientation Guide students in creating a descriptive title and labeling their axes appropriately. A good descriptive title might be: Mr. /Ms. Example s Class Carrot Taste Test Or you may choose to label according to a scientific question: Which carrot is the favorite of Mr./Ms. Example s 4th grade class? Label the horizontal axis: Foods Tasted Label the vertical axis: Number of Votes or Number of Students who Prefer Explain the connection between interval and scale and the importance of a neat and easily readable graph, which fills the entire sheet. Wrap up: Once you have completed the graph, ask students to refer back to their tasting chart and select a few volunteers to explain their choice for Food 1 or Food 2 based on their observations. Reveal the origin of each food and spend asking students to propose additional questions that you might ask to investigate the factors that 3

4 influenced the taste; items you may want to mention include soil fertility, growing practice, processing, packaging, distance travelled for distribution, weather, or other factors in the food system from farm to plate. Extensions: Almost any produce item such as apples, peppers, tomatoes, and greens (lettuce, kale, spinach, etc) can be compared in this way. You may also choose to compare recipes with slightly different ingredients (eg. garlic roasted squash vs. cinnamon roasted squash OR spinach salad vs. lettuce salad). Your hypothesis will vary from the examples provided in this lesson if you choose to compare recipes, which both utilize local ingredients. Credit for Adaptation Word Bank and Tasting Chart from Got Veggies? published by Community GroundWorks at Troy Gardens. Available in PDF form online at: 4

5 Sweet Fragrant Bitter Sour Sharp Healthy Ripe Sample Word Bank Zesty Mealy Firm Crunchy Tough Spicy Tangy Juicy Flavorful Squishy Zippy Acidic Earthy Rich 5

6 Tasting Chart Name of Fruit or Vegetable Look Smell Feel Taste Sound Tasting Chart Name of Fruit or Vegetable Look Smell Feel Taste Sound 6