Summary

In this activity, students will become familiar with the chemistry components of photosynthesis. They will use role-play and/or demonstrations to describe the purpose of photosynthesis in this activity.

Grade Level

Elementary School

NGSS Alignment

This activity will help prepare your students to meet the performance expectations in the following standards:

• 3-LS1-1: Develop models to describe that organisms have unique and diverse life cycles but all have in common birth, growth, reproduction, and death.
• 4-LS1-1: Construct an argument that plants and animals have internal and external structures that function to support survival, growth, behavior, and reproduction.
• 5-LS1-1: Support an argument that plants get the materials they need for growth chiefly from air and water.
• Scientific and Engineering Practices:
  • Developing and Using Models
  • Engaging in Argument from Evidence

Objectives

By the end of this activity, students should be able to

• Construct an argument that plants have internal (cells performing photosynthesis) and external structures (roots, leaves) that function to support survival.
• Understand that photosynthesis is a chemical change by which water and carbon dioxide are converted into oxygen and carbohydrates.

Chemistry Topics

This activity supports students’ understanding of

• Photosynthesis

Time

Teacher Preparation:15 minutes

Lesson: 45 minutes

Materials

• Seeds for demonstration
• Minimum of two fresh green tree leaves per group of 3 or 4
• Crayons or markers
• Poster paper
• Plain white paper

Safety

• Students should wash their hands thoroughly before leaving the lab.
• Check for allergy to trees prior to beginning the activity.
• Remind students that specimens should not be put in their mouth.

Teacher Notes

• Teachers should prepare in advance of this activity:
  • Organize students into small groups of 3 or 4
  • Copy rubrics for student to use during presentations. Each student will need a rubric for each group that presents.
  • Review video, and open website for video: Germination of Seed time lapse
  • Review video, and open website for video: Amazing Process Of Photosynthesis video
  • Print or have available image of plant cell.
  • Print or have available image of chloroplast.
  • Purchase Plant Cell Model (optional)
• This lesson is intended for 2nd-4th grade, but can be adjusted to fit the needs of older students.
• Background information: You may or may not need to share this information with students. It reviews that plants do need oxygen to perform cellular respiration.
• Misconceptions are numerous when teaching about photosynthesis. This article is helpful in avoiding the misconceptions:
• Kid friendly videos about photosynthesis:
  • Photosynthesis | The Dr. Binocs Show | Learn Videos For Kids
  • Photosynthesis | Two Little Hands TV | Educational | Kids Songs
• Other resources: AACT lesson for upper elementary
  • Plant Chemistry Lesson Plan
• Day 1 Phenomenon: The growth of a seed (i.e. acorn) to a tree (i.e. oak tree)
  • Ask the students how a tree grows from a tiny seedto a very large tree. Show a few examples of seeds-acorns, maple seeds (technical name “samaras” often called “helicopters” or “whirlybirds”), pine cones, and the mature trees each grows into.
  • Take the students on a nature walk to observe mature trees and their respective seeds.Instruct the students to each collect 2-3 green leaves. (Teacher may just use pictures of large trees if a nature walk is not possible and provide the leaves from home.)
  • Have the students rub the leaves on a sheet of white paper. Discuss what the green marks are following the rubbings. Name the green substance chlorophyll. If cell model was purchased you can show students chloroplasts. If not use this image.
  • Watch the video of Germination of Seed time lapse. Teachers should stop throughout the video to ask guiding questions about what the students think is happening. Be sure to note plants need water, sunlight. You will need this information to lead into the ‘ingredients’ for photosynthesis.
  • Watch the Amazing Process Of Photosynthesis video. Minute 2:07 shows carbon dioxide being used by the plant. For simplicity, you may want to mute the sound and narrate yourself. (If purchased from the optional model, show it at this time).
  • Using leading questions, guide the students to discover what other essential ingredients trees and other plants need to grow. (water, sun, carbon dioxide, oxygen).
  • Students Think-Pair-Share about what they have learned from the walk, discussion, and videos.
  • Direct students to draw a diagram of a tree and label the roots, stem, leaves.
• Day 2
  • Give a rubric sheet to each group. Review background information and components of rubric. You may choose to share this example with students. The authors included the clip for illustrative purposes for the teacher. Photosynthesis | Two Little Hands TV | Educational | Kids Songs
  • Explain to the students that each group of students will be creating a song, dance, play, poster, skit, or other project to demonstrate how a seed becomes a tree (or other plant) using the following vocabulary words: roots, stem, leaf, photosynthesis, chlorophyll, sun, rain/water.
  • Share the rubric that will be used to grade these projects so students understand the parameters they must meet.
  • Give the groups time to plan, prepare and practice.
  • When groups present their projects, students and teacher use the rubrics to score each group.