One of the major challenges for faculty teaching general chemistry is how to encourage students to practice solving problems. We know that for students to develop chemical intuition and problem-solving skills, they must "get their hands dirty" as they decipher and unravel problems inherent to our discipline. One tool that I've used since its release in 1996 is the ChemSkill Builder, an electronic homework package. The latest version, ChemSkill Builder (CSB) 2000, version 6.1, is an excellent, effective integration of teaching and testing most quantitative and conceptual learning objectives in an interactive way. It is inexpensive and easy to use for both students and faculty.

The CSB 2000 package of personalized problem sets, specifically designed to complement most general chemistry courses, is a program on CD-ROM for PC Windows users (3.1, 95, or 98), with more than 1500 questions and a 3 1/2-in. record-management disk. There is a separate grade-management disk for the instructor. It has 24 gradable chapters, each with 5 or 6 sections, plus two new chapters that are not graded: Polymer Chemistry and an Appendix of Chemical Skills. Each section begins with a short review of the topic and many have interactive explanations. If students miss an answer, they are given a second chance for 70% credit. If they still miss, the worked-out solution is presented in detail. Students can work each section as many times as they wish to improve their scores. Periodically, the students download their data directly into a PC set up by the instructor. The data can be easily converted into an ASCII file and merged with a spreadsheet. The use of CD-ROM solves the sporadic problems associated with previous versions on 3 1/2-in. disks: software glitches, failed disks, and system incompatibilities. The quality and number of graphics and interactive exercises are much improved in this latest version. I particularly enjoyed the interactive explanations of significant figures and dimensional analysis in Sections 2.3 and 2.5, the pH meter simulation in Section 18.3, the Geiger counter simulation in Section 23.5, and the new periodic table game in Appendix A.

I informally polled my Fall 1999 students on their midsemester impressions of the ChemSkill Builder, version 5.1--the previous version. The preliminary results in Table 1 show an overall acceptable rating of 3.45. Note that 51% of the students thought that incorporating the CSB into the syllabus was good to very good, compared to only 16% who gave negative responses. Positive comments included "a great tool to study for the test" and "it shows how to work out the problems". The major negative comment was that the CSB was too time-consuming because the acceptable answer had to include the right number of significant figures and the correct unit--sexactly what an instructor wants the student to learn.

Interestingly, the scores given appeared to be independent of the students' midterm grades, suggesting that acceptance of this product might be linked to a specific learning style. When I compared my students' responses to their Keirsey temperaments in Table 2, the ChemSkill Builder appealed somewhat more to the students who like activity, entertainment and immediate feedback (SP) or who enjoy technology and constant success experiences (NT) than to the students who prefer more group interactions (NF) or who need more structure (SJ).

At the semester's end, the students were asked again to rate the ChemSkill Builder, and 97% of 155 responses either agreed (28%) or strongly agreed (69%) that it proved helpful in learning course material. Moreover, 99% thought that I should continue to incorporate the ChemSkill Builder in future courses.

To summarize, the ChemSkill Builder 2000, version 6.1, will be an excellent tool for augmenting the learning process in the general chemistry classroom.