In this study I present RTA-2, a new modified version of the original analytical tool Realization Tree Assessment, RTA. The purpose of RTA is to assess students' mathematical concept development through realizations of mathematical objects. In the text, I present the commognitive framework upon which RTA is based, that deals with the individual's way of communicating within different discourses, in this case the mathematical discourse. Due to the limitations of RTA, where area of use is one, I present some modifications for the RTA which results in the new RTA-2. To show that RTA-2 has the same purpose as RTA, but with a larger area of applicability on normal lessons, I applied the new tool on 9 high school mathematics lessons, which gave two results. The first result was that Swedish high school students' opportunity to realize mathematical objects for conceptual development. The second result was that RTA-2 is more usable for normal lessons and that the modifications provide an opportunity to understand why students do or do not realize objects.