Girl-from-Mars you are looking in Latvian I have no idea, but there are some interesting based on true stories in English for example maybe they are translated in Latvian and nicely illustrated.
- The Water Princess, by Susan Verde. A story about the girl who wanted to bring fresh water to the community.
- The Watcher: Jane Goodall’s Life with Chimps. From London to Tanzania and about Chimpanzees
- Miss FOX'S Class Goes Green. About simple actions like saving energy, water, recycling.
- The Lonely Polar Bear. About the bear in Arctic.
- Plastic Sucks! By musician why plastic is bad.
- My First Heroes: Eco Warriors. About Greta Thunberg, David Attenborough and a couple others.
Probably like books What is climate change, The Planet Earth, Greta's book kids version, and many more you can find. Reading together, answering questions, giving relevant examples.