There are several schemes throughout history and across the globe that could be considered "child migration" schemes, each with different purposes and impacts. Some examples include:
* Historical child migration schemes: These often involved moving children from impoverished areas to wealthier countries, often with the aim of providing them with better opportunities or to alleviate overpopulation in their home countries. Examples include the "orphan trains" in the US in the late 19th and early 20th centuries, and the "child migration" schemes to Australia, Canada, and the UK in the early 20th century.
* Modern child migration schemes: These can involve the movement of children for various reasons, including reunification with family members, seeking asylum, or escaping conflict or poverty.
To provide you with a more specific answer, please specify:
* The timeframe you are interested in: Are you interested in historical schemes or contemporary schemes?
* The geographic location: Which country or region are you interested in?
* The specific purpose of the scheme: Are you interested in schemes related to adoption, fostering, asylum, or other reasons?
Once I have this information, I can give you a more accurate and detailed answer.