ABSTRACT Childhood obesity continues to be a serious public health issue in the United States (US), with disproportionate rates among low-income, minority children. Effective, yet engaging interventions need to be designed to capture the attention of children and their parents/caregivers living in a multi-media environment. Our work demonstrates the novelty, appeal, and effect of multi-modal narratives in the form of comics, which convey messages in graphics and minimal language, as a format to deliver health messages to the younger populations. Additionally, interventions delivered on web-based/mHealth platforms can be engaging and scalable to support health behavior change in families and also enhance and extend the impact of clinic visits by providing online resources that reinforce health messages delivered in-person by healthcare providers. In collaboration with our community partner, Children’s Aid (one of the oldest and largest US child welfare organizations), an AHRQ-funded R21 study supported development and pilot testing of Intervention INC, a family-centered, interactive, web-based health promotion tool focused on reducing childhood obesity risk. The tool is tailored to meet the needs and preferences of low-income, black/African-American (AA) and Latino children ages 9 to 12 and their parents/caregivers. Results of a pilot feasibility study were highly promising as not only was the tool feasible to deliver and acceptable to our child and parent populations, children receiving the comic tool demonstrated greater improvements (p<0.05) in vegetable, water, and sugar intake compared to the control group, from pre- to post-intervention. However, knowledge gaps regarding tool effectiveness and implementation in real world settings still exist. To fill these gaps, we propose a study with the following aims. In Aim 1, formative research will be conducted with healthcare practitioners/administrators and child-parent dyads to identify organizational (clinic) and family characteristics relevant to implementing such a tool in a clinic setting, while in Aim 2, the tool will be adapted (based on Aim 1 findings) and usability testing of it will be conducted. In Aim 3, a full-scale RCT will be conducted in Children’s Aid community clinics, to test the effect of the adapted and extended tool, which will comprise a 12-week comic intervention and a 6-month maintenance intervention, on child BMI z-score. In Aim 4, contextual factors at the clinic-, provider-, and family-level that influence tool implementation will be explored. We believe that this family-centered web-based tool is unique given its focus on innovative communication approaches and mHealth platform to enhance accessibility and engagement with an often hard to reach, diverse population. It also has strong