This film examines the tell-tale signs of air pollution and how its effects can be catastrophic to ecosystems. People and places -Human impact on the environment - Polluting the air Learning Points Acid rain and holes in the ozone layer are both effects of air pollution. A Twig Curriculum Film. Delivering key learning points. Get straight to the facts in just three minutes – directly linked to core learning, Twig's curriculum films will fit neatly into your lesson plans.