Petal And Ben's Adventures In Thailand

A collection of three short stories. Petal and her little brother, Ben, moved to Thailand. They didn't like Bangkok, but their house by the sea was much better. A nine-headed snake scares them, but they soon teach him a lesson. The next tale encourages them to deal with rubbish scarily. Book three - they go to a new school. Why was everyone using mobile phones, but Petal and Ben were not allowed?