+ 5 volts I
Figure 4. Schematicdiagram of receiver and computw imerface.
Figure 3. Schematic diagram of delenor and Iransminer have led to the unreliahility of data transmission. It should also he noced that theschmitt trinner naveeitherarerostate or one state, dependingupon whetherthe input was larger or smaller than a threshold voltage. Therefore, for a quantitative measurement of an analog input signal, an AD converter card is needed.
The Group-ot-Three Phenomenon: Does It Work With Computers? Gem Rayner-Canham
Sir Wilfred Grenfeli College Corner Brook. NF, A2H 6P9, Canada During the use of our computer-assisted drill program (14). we received requests from students to be permitted to work in pairs. This h a s to allow them to discuss problemsolving methods with each other. We noted that a three-way interaction seemed to develop hetween the two students and the computer. A similar observation of group work has been made concerning a drill program in biology (15). This threeway interaction brought to mind some previous work that showed students work best in groups of three (16). It is possible that the same principle is working in our case, but with the computer being the third component.
The concept of students working individually a t terminals seems to be generally accepted. Perhaps this is due to the "loner3'-type personalities of earlier computer enthusiasts. The student-nair method warrants further investieation. Not only did seem to promote learning, but it also seemed to overcome the reticence of comauter-nhobic students. who no longer had to face the machine alone.4
ii
Literature Clted 1. Mmre,J. W.;Brwks.D.W.:Fuller.R.G.:Jensen,D.D. J. Chem.Educ. 1977,54,276. 2. Johnson,K. J;Vm Willia, W.;Seely,O., Jr.; Moore, J. W.J. Chem.Edue.1981.58.177. 3. Aikens.D.A.:Baiiey,R.A.:Giaehino,0.0.:Moore, J.A.:Tomkins,K.P.T.Inregrorod Ezperimenfm Chamisfry: Allyn & Bseon: Boston. 1976;Vol. 2. Chapter 52.
4. Shoemaker, D.; Gsr1and.C. W.; Steinfe1d.J. I.; Nibler, J. W. Experiments inPhysied Chemistry, 4th ed.: MeGrsw-Hill: Near York, 1961: Chapter 8. 5. nanieb,~.: w i ~ l i ~~ .~ ;~B, ~~ ~. ~ ~ ~ , P . ; A I ~ ~ ~ ~ ~ , RJ.E. .A.:c~~~~~I ExpmimentdPhy8tcal Chemistry. 7thed.:McGrav-Hill: Near York, 1970: Chapter 6. 6. Ref. 3, Chapter 22. 7. Ref. 4. Chanter 7. 6. Ref.5;chapter 4. 9. Ref. 3, Chapter 26. 10. Herbrsndaan. K. F. J. Chem. Edue. 1971,48,706. 11. Ref. 3,Chapter35. 12. Young,J. A,; Zefo,R.J. J. Cham.Educ. 1958.35.146. 13. Lehmao, J. R. J. Chsm. Educ. l985.62(6), 49fA99. 14. bynor-Csnhsm, G. W.: Dickie, W.J. Computers Moth 15. Capri0.M. W.J. Co1l.S~;. Teach. 1985.15.87. 16. Taylor, T. E.J. Coll. Sei. Teach. 1976.5, 320.
A s pointedout by areviewer,there will still be those who preferto work one-on-one with the computer. In fact, it would be interesting to correlate personality type and academic ability with preference for single or pair working.
Expanded MlCROgram Newsletter Now Available The EPIE Institute has announced thst they have expanded their existing newsletter, MICROgram, to indude monthly information on up to 175newly cataloged programs that they have added to the EPIE data base in previous weeks. This change was necessitated hy the rapid growth in computer programs thst originally were described on an annual basis in the EPIE publication TESS(The Educational Software Selector). The MICROgram software descriptions include suhjeet area, program type, grade level, computer compatibility, price, summary of operation, and ordering information, In addition, the expanded MICROgrom continues to report on current topics and issues in computer-oriented education and offers subscribers the opportunity to order EPIE PROIFILE's, comprehensive individual evaluations of selected courseware. Also, the new MICROgrarn contains a listing of citations to software reviews by other reviewing agencies newly added to EPIE's database and the option for subscribers to send for the full text of reviews. Subscriptions to MICROgram are $55 or $50 if purchased with the four-volume 1988-1989 edition of TESS-The Educational Software Selector. TESS is EPIE's comprehensive guide to educational software programs and publishers. For further information or to place an order, write EPIE Institute, P.O. Box 839, Water Mill, NY 11976. Or call (516) 2834922.
Volume 65
Number 4
April 1988
345
