With computers, tangible tools are represented by the hardware (e.g., the central processing unit, scanners, and video display unit), while intangible tools are represented by the software. There is a special category of computer-based software tools (CBSTs) that have the potential to mediate cognitive processes--computer-based cognitive tools (CBCTs). Only a limited number of CBSTs have been designed specifically for educational purposes. It is the design of the educational environment, specifically the educational intent, that transforms student interactions with a CBST to that of a CBCT. Two examples of CBCTs are described. The Interactive Graphic Tool (IGT) facilitates on-screen sketching of graphs. Students receive qualitative feedback, may revise their articulation of graphical knowledge any number of times, and ultimately have access to expert answers for comparison and self-evaluation. The Text Analysis Object (TAO) also facilitates an iterative approach to knowledge construction. The TAO allows a student to type extended answers to questions, receive qualitative and limited summative feedback, and access to both expert and "good student answers" for comparison and self-evaluation. (Contains 15 references.) (Author/AEF)