Collins, Shalea and O'Leary, Amy. "Kindergarten Math- Simple Addition". OER Commons. Institute for the Study of Knowledge Management in Education, 28 Jan. 2018. Web. 26 Nov. 2024. <https://oercommons.org/authoring/26830-kindergarten-math-simple-addition>.
Collins, S., & O'Leary, A. (2018, January 28). Kindergarten Math- Simple Addition. OER Commons. Retrieved November 26, 2024, from https://oercommons.org/authoring/26830-kindergarten-math-simple-addition.