Mermaid School: Save Our Seas! (okładka  miękka, wyd. 09.2021)

Marnie Blue is shocked when lots of plastic rubbish starts to appear in Mermaid Lagoon. It`s causing all sorts of problems and even harming the underwater animals. Marnie and her friends decide enough is enough and they must have a big green clean-up. But just where is all the plastic coming from? With the help of the local Brinies group, a new dolphin pal and a human friend, the mermaids come up with a plan to rid the lagoon of plastic junk for good.