Background: Computational thinking (CT) is a way of thinking that helps children solve problems and complete tasks in more organized ways, using computer science skills. Prior research indicates that promoting CT skills in young children can support the acquisition of general problem solving (PS), executive function (EF), and social emotional learning (SEL) (Bers et al., 2022; Falloon, 2016; Myers, 2021). Most research on the acquisition of CT skills in young children has focused on coding interventions or unplugged curricula. This poster describes a randomized controlled trial (RCT) to investigate the impact of videos, games, and hands-on activities from "Work it out Wombats! (Wombats)," an animated public media series, on young children's CT skills, PS, and SEL skills. The study is designed to meet What Works Clearinghouse (WWC) standards, Version 5.0, without reservations (WWC, 2022). Research Questions: This study has three main research questions--(1) Does providing 8 weeks of access to "Wombats" resources via an internet-enabled tablet improve low-income 4- and 5-year-old children's "computational thinking skills" as compared to providing an internet-enabled tablet that cannot access "Wombats" resources? (2) Does providing 8 weeks of access to "Wombats" resources via an internet-enabled tablet improve low-income 4- and 5-year-old children's "problem-solving skills" as compared to providing an internet-enabled tablet that cannot access "Wombats" resources? and (3) Does providing 8 weeks of access to "Wombats" resources via an internet-enabled tablet improve low-income 4- and 5-year-old children's "SEL skills," as compared to providing an internet-enabled tablet that cannot access "Wombats" resources? Setting: This study measures the impact of access to "Wombats" in a home environment or other informal setting. To ensure a geographically and demographically diverse sample, we collected data in seven U.S. locations: New York, NY, Chicago, IL, Philadelphia, PA, Los Angeles, CA, Houston, TX, Washington, DC, and Waltham, MA. Data were collected at two in-person visits. Participants: This study included approximately 450 4- and 5-year-old children from low-income households. Inclusion criteria were: (1) child does not watch "Wombats" more than four times in a typical week, (2) only one participating child per family, (3) the child is able to participate in an English-language assessment that requires verbal responses, (4) the child is aged 4 or 5 as of December 1, 2023, (5) the family's annual household income is less than $80,000 or the family is eligible for public programs, and (6) a parent can receive SMS messages. Intervention: Both the treatment and control groups received data-enabled tablets for the 8-week study, and information about the study and tablets. To prevent contamination from outside exposures, tablets for both groups blocked publicly available PBS KIDS and "Wombats" webpages and the PBS KIDS video and game apps. The treatment group intervention consisted of "Wombats" media resources viewable on a study app on the tablet including videos, games, and hands-on activities. The research team recommended using the resources for about 1.5 hours per week. To maintain child engagement throughout the study, a new set of "Wombats" videos appeared on the treatment group study app once per week. The study app also delivered "Wombats" digital games on a delayed schedule. Four "Wombats" hands-on activities were available for families throughout the entire study. Treatment group parents received text messages encouraging them to engage in the resources, report how much their child spent using the tablet in the past week, and to watch two parent videos related to "Wombats." Families assigned to the control group received an orientation to the study and was instructed to view educational media of their choice for about 1.5 hours per week. Control group parents received text messages reminding them to use educational media on the tablet and to report how much time their child spent using the tablet in the past week. Research design: Random assignment to the treatment and control groups took place after the child completed the pre-test assessments and a parent completed the pre-survey. We block-randomized participants to condition by site, to ensure an even balance of children in the treatment and control condition at each site. Data collection and analysis: Main outcome measures are: (1) STEM+C (Dominguez et al., 2022): a hands-on assessment of CT for preschool-age children. It includes a series of developmentally appropriate assessment tasks designed to elicit young children's understanding of CT skills and concepts, including abstraction, algorithmic thinking and sequencing, debugging, and problem decomposition. Administered at pre- and post-test. (2) Picture problem solving task (Fusaro & Smith, 2018), a measure of children's general problem-solving ability, which asks 4- to 5-year-old children to think through novel problem scenarios. Administered at posttest only. (3) PROMIS EC (Blackwell et al. 2022), a parent-report measure that assesses the engagement and selfregulation of children ages 1 to 5. Administered at pre-and post-test. Our analysis of main outcomes will use the following ordinary least squares regression model: Y = [beta][subscript 0] + [beta][subscript 1]TRT + [beta][subscript 2]pretest + [beta][subscript 3]covars + [beta][subscript 4]site + [epsilon]. Where Y represents the outcome of interest, [beta][subscript 0] represents the intercept; [beta][subscript 1]TRT is a dummy variable equal to 1 if the child was assigned to the treatment group and zero if assigned to the control group; [beta][subscript 2]pretest represents the child's pre-test score on the outcome of interest; [beta][subscript 3]covars represents a vector of child and family demographic characteristics and baseline child EF, [beta][subscript 4]site represents the child's site, and [epsilon] represents the error term. We will include the following covariates in the model unless there is evidence of multicollinearity: pretest of the outcome measure being assessed, site, child gender, child age in months, child grade, child race or ethnicity, child's primary home language, child has an IEP or 504 plan, family annual income, parent education, prior exposure to "Wombats," and baseline EF. In addition, we will report bivariate correlations among all outcome measures.