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Inquiry & Experimentation
Seed Structures
Change over time
Conditions for Germination & Growth
Typicality
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Growth Rate
Order and Timing of Events
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    Inquiry & Experimentation
    Overall Objective
 

To introduce scientific inquiry in the classroom, from generating research questions to designing studies, collecting and interpreting data and supporting claims.

 
    Lessons
 
 
    Generating seed questions
    Objective
 
To introduce scientific inquiry by generating students' questions about seeds.
   Overview of Lesson
 

Following the pre-assessment task, students discuss what they already know about seeds and generate an initial list of questions about seeds. We encouraged "I wonder." questions and asked, "What do we want to find out about seeds?" Student questions were recorded on large chart paper along with the initials of the student who posed that particular question. Attributing each question is important when other students "piggyback" on an idea or ask classmates to clarify an idea. The list of questions is dated because this task is repeated over the course of the unit. As the students dissect seeds and watch germination taking place they pose new questions and propose more sophisticated investigations. These lists of student questions provide us with valuable information about how thinking is progressing and allow students to "see" how their ideas about seeds have changed and grown.

   Children's Thinking Druing Lesson
 

The list of seed questions brainstormed by students at the beginning of the unit shows that they possess little detailed information or in-depth knowledge of seeds. More than one child asks, "Where do seeds come from?" When asked to wonder about seeds, several students focus on how seeds react to extreme conditions. Responses that fall into this category include questions such as "How do seeds survive underground?" "What happens to seed covered by lava?" and "How do seeds survive earthquakes?" There is always interest in record breakers so one student asks, "What is the smallest seed in the world?" and another wants to know, "What's the biggest seed?" Some students think about the drawings they made of the inside of a seed and then pose questions that test their intuitions about a seed's structure, such as "How many layers does a seed have?"

During this early questioning time, it is difficult for students to distinguish between "plant" questions and "seed" questions. The question "How many sunflower seeds are on one sunflower?" leads to "How high can a sunflower get?" Their limited knowledge and lack of hands-on experiences to this point makes it hard for the students to remain focused on the idea of seeds and sustain the inquiry. When the teacher pushes the class to extend their list of questions a student wonders, "How many seeds can you fit in your mouth?"

After only a few days of observing the seeds in their germination bags, it is much easier for the class to generate a list of questions. Some of these new questions reflect a desire to explain developments the students are noticing:

  • " How do roots pop out of a really hard shell?"
  • " How does the seed break in half?"
  • " Are there hairs on roots?"
  • " Can the second layer [of a seed] be a different color than the first layer?"
Other questions show an increased interest in timing:
  • " How long does it take a root to grow from a seed?"
  • " How long does it take for a seed to get the first layer off?"
New questions such as these indicate that curiosity about seed survival remains strong:
  • " Can a seed melt from the sun?"
  • " Can a seed dry up after planting and still grow?"
  • " Do some kinds of seeds 'hibernate' for the winter?"
Over the next several days, the class considers questions such as:
  • " Will seeds grow in the dark?"
  • " If a seed breaks in half, will there be two halves [of a plant], or just one?"
  • " Will an embryo grow on a water agar plate without its food?"
Only a couple weeks after beginning the seed unit, individual students and small teams of students are posing a wide variety of interesting questions about seeds. They are pursuing questions that they themselves can investigate and attempt to answer:
  • " Will bigger seeds grow faster?" (giant limas compared to regular limas)
  • " Will roots grow in different directions if we point the seeds in different directions?"
  • " Will roots grow out of every side of the seed?"
  • " Will seeds grow 'squished up'?" (many seeds per pot)
  • " Will seeds grow if soaked in salt water?"
  • " How much can corn roots grow in one day?"
  • " Will the shoots growing from different colors of Indian corn be different colors?
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Last Updated: February 17, 2005
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