Phenology is both fun and practical. The data phenologists gather can help predict when to plant crops, when allergy season begins, when to look for and treat invasive species and plant pests, and how living things are responding to climate change.
With a little training, anyone can collect phenological data. A variety of community scientist projects are open to volunteers of all ages and walks of life. See the website for the USA National Phenology Network and choose any of the links to Nature's Notebook, the tool they use to collect data.