Science · Class 10

Active learning ideas

Coordination in Plants: Tropic Movements

Have you ever noticed how a plant kept indoors seems to lean towards the window? This topic explores the amazing, silent ways plants move and grow in response to their surroundings.

• CBSE Learning Outcomes
• NCERT: Class 10 - Chapter 7 - Coordination in Plants

• 10–20 min
• Pairs → Whole Class
• 3 activities

Activity 01

• Experiential Learning
• 20 min · Small Groups

The Shoebox Maze for Light

Grow a small bean plant inside a shoebox with internal partitions forming a maze and a single hole for light at one end. Students will observe how the plant shoot navigates the maze over a week to grow towards the light source.

Explain how phototropism helps a plant survive.

Facilitation Tip

Ensure the box is completely sealed except for the light hole to get a dramatic effect.

What to look for

Give students diagrams of plants responding to different stimuli (e.g., a plant in a dark room with one window) and ask them to identify the stimulus, the type of tropism, and whether it is positive or negative.

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

Activity 02

• Experiential Learning
• 15 min · Pairs

The Sideways Seedling Jar

Germinate a few seeds (like gram or bean) on moist cotton wool inside a transparent glass jar. Once the radicle and plumule appear, turn the jar on its side and observe for a few days how the root continues to grow downwards and the shoot bends to grow upwards.

Compare geotropism in plant roots and shoots.

Facilitation Tip

Use a transparent jar so students can observe the root and shoot growth without disturbing the setup.

What to look for

Ask students to write a lab report on an experiment they conducted to demonstrate phototropism, including their hypothesis, method, observations, and conclusion explaining the role of auxin.

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

Activity 03

• Experiential Learning
• 10 min · Individual

Tendril Touch Test

Provide students with a small climber plant, like a pea plant, and a thin stick or pencil. Students will gently touch a tendril to the support and observe over 2-3 days how it coils around the object, demonstrating thigmotropism.

Identify the stimulus for hydrotropism and thigmotropism.

Facilitation Tip

This is a long-term observation; ask students to take daily photos or draw the changes they see.

What to look for

Provide a checklist with statements like 'I can define geotropism' or 'I can explain why shoots grow towards light'. Students rate their own understanding on a scale of 1 to 3.

• Apply
• Analyze
• Evaluate
• Self-Awareness
• Self-Management
• Social Awareness

A few notes on teaching this unit

Begin with a simple observation of a classroom plant. Use the 'shoebox maze' experiment as a central activity to provide a clear, memorable demonstration of phototropism. Emphasise that this is a slow growth process by having students record observations over several days. Use diagrams to explain the role of the hormone auxin, showing how it concentrates on the shaded side to make cells grow longer.

Through these hands-on activities, your students will be able to explain and demonstrate how plants use directional movements, known as tropisms, to find light, water, and support for their survival.

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Watch Out for These Misconceptions

• Plants 'think' or 'decide' to bend towards the light.

  Plant movements are not conscious decisions. They are automatic growth responses controlled by chemical hormones, like auxin, which react to environmental stimuli.

• All plant movements are tropisms.

  Tropisms are directional growth movements. There are also nastic movements, which are non-directional, like the folding of leaves of a 'touch-me-not' plant, which is a response to touch but not related to the direction of the touch.

• Roots grow down only because they are heavy.

  While gravity pulls everything down, roots actively grow downwards in response to the stimulus of gravity. This is an active process called geotropism, not just a passive falling.

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Methods used in this brief

• Experiential Learning