Assessment of children has always been a significant part of the educational fabric of schooling. More recently, a focus of debate has been whether we are assessing our children too much. In the UK, this debate has emerged through considerations of the impact of a well-established system of national curriculum testing for 7-14 year olds, and the introduction of modular qualifications for 16-18 year olds. Thus, children from a very early age are exposed to formal, high-stakes testing situations which continue across all their years of schooling. This debate has culminated more recently with political, academic and policy level concern that children are suffering unduly through the amount of testing that they have to go through and that too much testing has adverse consequences for their overall experience of schooling. The linkage between the impact of assessment and compliance with children’s rights is a connection, which although seemingly obvious, is nonetheless rarely made, particularly by governments, which, as signatories to the relevant International Treaties, have the primary responsibility for ensuring that educational practice is compatible with international children’s rights standards. While some jurisdictions are explicit about an adherence to children’s rights frameworks in general policy documentation, such a commitment rarely features when the focus is on assessment and testing. Thus, in spite of significant public and academic attention given to the consequences of assessment of children and governments committed to working within children’s rights standards, the two are rarely considered together. This paper will examine the implications of international human rights standards for assessment practice. Key children’s rights principles and standards will be used as a critical lens to examine assessment policy and practice. The overall aim is to seek new insights into the complexities of assessment practice from the critical but neglected perspective of children’s rights.