From site:
ACD/Labs has long been committed to helping the academic community provide future scientists with access to software that many will use throughout their chemistry careers. ACD/ChemSketch is a state-of-the-art chemical drawing software that we provide freely to students to initiate them into the world of chemical structure drawing, nomenclature, and property prediction at a high-level...
This software package is well suited to illustrate a variety of chemical concepts, and includes powerful optimization and 3D visualization tools as well as numerous chemical templates. Drawing molecules, reactions, and schematic diagrams could not be easier!
Here is an introductory guide to ChemSketch.
