Understanding variations in children's well-being is key to addressing inequalities. It is especially useful to understand children's own perspectives, although there is a lack of short questionnaires using simple language which can be administered to younger children (or in situations when testing-time is limited). Here we first present the VSWQ-C, a Very Short Well-Being Questionnaire for Children, which captures health-related quality-of-life in a brief questionnaire for both older and younger child responders. We provide preliminary validation evidence for this new measure from two English samples of children aged 6-7 and 9-10 years. Next, we also adapted an existing measure of children's emotional well-being (10-item Positive and Negative Effect Schedule for Children; Ebesutani et al., 2012), again to be suitable for a younger cohort. Our adaptation, the Definitional Positive and Negative Effect Schedule for Children (dPANAS-C), provides children as young as 6 with age-appropriate definitions of questionnaire vocabulary. We again present preliminary validation evidence from 9-10 year olds, as well as children 6-7 years (i.e., 1-2 years younger than the original version of this questionnaire had been psychometrically developed for). We looked too at demographic influences, and show that older children report greater well-being (in the VSWQ-C) as well as lower negative affect (in the dPANAS-C), but without gender differences. Our findings show that our tools eliciting self-reports of well-being are valuable and valid instruments for children as young as 6 years, with acceptable reliability and strong convergent validity. (PsycINFO Database Record (c) 2020 APA, all rights reserved).