UN and international human rights law is a vast and complex topic. Please follow the links below to the different major topics. The first one - on taking cases to the UN - is by the far the most extensive. Good luck with the international law - it is daunting!
Taking your case to the treaty bodies and committees
Universal Periodic Review
Commission on the Status of Women
For more information please also visit the pages of the highly useful Bayefsky.com database.
In the case of child rights specifically, it is highly recommended to also consult the Childs Rights Information Network(CRIN) and the NGO Group for the CRC