1. Investigating the effects of pollution on plant growth: Set up an experiment where you expose plants to different types of pollution, such as air pollution or water pollution, and observe their growth over a period of time. Compare the growth of the polluted plants to those in a controlled environment to determine the impact of pollution on plant health.

2. Testing the pollution levels in different water sources: Collect water samples from various sources, such as a river, a pond, and tap water, and test them for pollution levels. Use simple testing kits or equipment to measure parameters like pH, dissolved oxygen, and presence of pollutants. Analyze and compare the results to determine the pollution levels in different water sources.

3. Investigating the impact of pollution on air quality: Set up air quality monitoring stations in different locations, such as near a busy road, a park, and a residential area. Use air quality monitoring devices to measure parameters like particulate matter, carbon dioxide levels, and air quality index. Compare the results from different locations to determine the impact of pollution on air quality.

4. Studying the effects of pollution on animal behavior: Observe and record the behavior of animals, such as birds or insects, in polluted and non-polluted environments. Compare their behavior, such as feeding patterns, mating rituals, or migration habits, to determine if pollution affects their natural behaviors.

5. Investigating the impact of pollution on water quality: Collect water samples from different sources, such as a river, a lake, and a polluted area, and test them for water quality parameters like pH, turbidity, and presence of pollutants. Compare the results to determine the impact of pollution on water quality and its potential effects on aquatic life.

Remember to always prioritize safety and follow ethical guidelines when conducting experiments involving pollution.