The Common Core State Standards for Mathematics (CCSSI 2010) expect second grade students to "fluently add and subtract within 20 using mental strategies" (2.OA.B.2). Most children begin with number word sequences and counting approximations and then develop greater skill with counting. But do all teachers really understand how this occurs? Have teachers been given ample opportunities to understand how this progression of early numeracy develops? This article encourages teachers to appreciate the complexity of counting and adding skills by viewing them through the lens of an early numeracy progression.