Number sense is one's ability to understand what numbers mean, perform mental mathematics, and look at the world and make comparisons. Researchers show instruction that teaches children how to classify numbers, put numbers in sequence, conserve numbers effectively, and count builds their number sense skills. Targeted instruction that teaches children to count in a flexible manner increases number knowledge, therefore improves number sense. A common manner of providing targeted instruction for children who have mathematics difficulties is called explicit instruction. Explicit instruction that utilizes objects and pictures teaches conceptual and procedural knowledge for specific mathematical skills. Researchers show explicit instruction improves mathematical skills which range from place value to algebra equations for students who have mathematic difficulties. The purpose of this case study was to explore and investigate if further research should be conducted on the use of explicit instruction to teach young children counting skills that lead to flexibility with numbers. Results and implications are discussed. Number sense is a developing construct that refers to children's fluidity and flexibility with numbers, the sense of what numbers mean, and the ability to perform mental mathematics, and the adeptness to observe the world to make comparisons (Berch, 1998). Difficulties with numeracy (i.e., number sense) interfere with acquisition of math skills (i.e., number operations and fractions) later in childhood (Clarke & Shinn, 2004; Mazzocco & Thompson, 2000; Van Luit & Schoman, 2000). According to Berch (2005), researchers have not come to a consensus of what number sense is; however, Jordan, Kaplan, Olah, and Locuniak (2006) identified key elements of numeracy. They are mathematical skills such as counting, number knowledge, number transformation, estimation, and the ability to create and identify number patterns.