Students explore the effects of pollution on aquatic habitats. They test the pH levels of various chemicals and infer how acid rain might affect aquatic ecosystems. They also investigate an algae bloom, conducting an experiment to determine which chemicals are catalysts for algae growth. Students then investigate the effects of different chemicals on seed germination.

Student Resources

• 6.1 Vocabulary
• 6.2 What Pollutes the Pond?
• 6.3 Acid or Base?
• 6.4 How Does the Amount of a Chemical Affect Algae Growth?
6.5 Do Chemicals Affect Seed Growth?6.6 Section 6 Assessment
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Learn by Reading

For additional content-area reading, check out the Houghton Mifflin Science eBook: Grade 3, Unit B, page 34; Unit C, page 61.