The Pennsylvania State University partnered with the Lebanon County Head Start Program to develop a set of progress-monitoring measures to assess key early literacy and mathematics skills for 3-and-4-year old children enrolled in Head Start. The project carefully developed skill probes in the early literacy domain (including alphabet recitation, letter identification, letter-sound correspondence, and phonemic awareness) and in the early mathematics domain (including number recitation, number identification, counting, and subitizing). Participants included approximately 200 Head Start children per year. The measures developed for this study can help ensure that children are developing key literacy and mathematics skills and can provide data regarding when a child is at risk of later academic difficulty and would benefit from change in instruction.