As young children make sense of mathematics, they begin to see with new eyes. What once was uncertain may now be determined. Objects become countable; fingers become tools; and numbers become more than just names. Educators revel in such developments--which mark significant progress toward more sophisticated understanding of number--and work tirelessly with children who struggle in this regard. These initial understandings of numerals, number words, and quantity hold special significance. Given that mathematical learning is considered cumulative in nature because existing concepts provide the basis from which increased levels of sophistication may be achieved, whole-number and arithmetic operations provide the foundation for future learning within the discipline. In this article, the authors use transcripts from video-taped records of one-on-one intervention sessions with two low-attaining first graders. They contrast the strengths and weaknesses of the students with respect to different aspects of number (quantitative, symbolic, and verbal). The article concludes with a discussion of the instructional implications. (Contains 5 figures.)