Using a Computer Screen as a Whiteboard while Recording the Lecture as a Sound Movie

Transcription

1 Usig a Computer Scree as a Whiteboard while Recordig the Lecture as a Soud Movie Joatha Lewi Keesaw State Uiversity Abstract The purpose of this presetatio is to demostrate the process of usig a laptop computer scree as a whiteboard, while, at the same time, recordig all scree activity, ad everythig that is beig said, as a soud movie. The result is a clear, complete, ad reliable set of lecture otes that the studets ca pick up from the istructor s web site, ad also a complete movie recordig of the actual proceedigs of the classroom. Whe viewig a movie, studets have the optio to pause it at ay time while they collect their thoughts; or they ca pull the cursor back ad forth to view the specific parts of the movie that are most importat to them. The movie recordig of each lecture, ad other course materials, are made available o a CD which is duplicated i a CD copier, ad is ready to be picked up by the studets very soo after the lecture eds. Lecture material is writte with Scietific Workplace or Scietific Notebook which combie the advatage of a dyamically produced clear ad complete set of lecture otes with istat access to a computer algebra system. The movie is created, either with the recordig utility i Camtasia Studio by TechSmith, or by ScreeCorder 4byMatchware.Thethe CD is mastered by the MeuMaker utility i Camtasia Studio ad, withi miutes, a complete, friedly self-cotaied CD has bee mastered ad ca be carried to the istructor s CD copy machie. The presetatio will demostrate how these software products ca be used to produce the results that have bee described here, ad will discuss the advatages of givig studets the optio of duplicatig the actual lecture room experiece rather tha merely readig a set of lecture otes. The author wishes to express his appreciatio to Dr. Laurece I. Peterso, Dea of the College of Sciece ad Mathematics of Keesaw State Uiversity, without whose support ad ecouragemet, the work described i this paper could ot have take place. 1

2 1 Itroductio: Techology for Commuicatio The use of techological tools i the teachig of mathematics has come to be idetified, largely, with the use of computig tools such as computer algebra systems ad had-held calculators. Accordigly, the programme of a typical techology coferece bristles with presetatios o the use of various computer algebra systems ad o the use of had-held calculators to ehace the teachig ad learig of mathematics. The author of this paper recogizes that such techological tools ca have eormous value of uder certai coditios, but feels that the mathematical commuity has take too arrow a view of techology ad has pluged headlog ito a orgy of computer algebra ad calculator use that is out of proportio to its true value. I am cocered that some mathematics courses are losig their frame of referece ad abdicatig their resposibility to teach the uderstadig of mathematical ideas ad priciples as they cotiue to look for ew ways to embellish the material with the use of computer algebra systems. I am also cocered that some mathematics curricula ad techology cofereces may be subsidized by those whose computig products would be featured i them ad who therefore have a fiacial iterest i the cotet beig preseted. There is a dager that the academic itegrity of such curricula or cofereces may, i some cases, be taited. This paper presets suggestios for a differet role of techology, a role of commuicatio. I discovered some years ago that it is possible to trai oeself to write with a efficiet scietific word processor much more rapidly ad effectively tha ayoe ca write o a chalkboard. I started producig my lectures by typig ito a laptop computer ad projectig my image oto a scree, ad I foud that I could geerate a set of lecture otes that was vastly more readable, complete, ad precise tha aythig that could be writte o a board, while still havig the beefit of beig the actual otes that were created durig the teachig process i the classroom. I this way, I could free my studets from the resposibility of compilig the otes while they are also tryig to absorb what I am sayig to them, ad I could guaratee that the otes o which they based their studies were complete ad reliable. Furthermore, sice the otes thus created could be read both as hard copy ad o the computer scree, where use of a computer algebra system happes to be appropriate, I ca make my otes iteractive with the help of the computer algebra systems that are budled ito the mathematical word processor that I use. The, about three years ago, I took the ext logical step ad started recordig the etire process as I teach i the classroom. I use a recordig utility that ca record ay chose regio of my computer scree ad, i this way, I produce a soud movie reproductio of my lectures, exactly as they take place i the classroom. Thus, studets who are havig trouble workig through their lecture otes have the optio of a virtual re-etry to the classroom to receive ay chose item of the material agai i a lecture eviromet. Withi a few miutes of the ed of each of my lectures, I have mastered a CD that cotais the complete set of lecture otes give, to date, i the course, ad cotais the

3 movie recordig of the latest lecture. The master CD is carried to my office where I have a CD copy machie ad, a few miutes later, I am placig CDs o a table for the studets to pick up. Each studet receives a CD for each time that the class meets. Software Issues.1 Usig The Computer Scree as a Whiteboard My solutio to the problem of usig a computer scree as a whiteboard is to type ito a Scietific Notebook or Scietific WorkPlace 1 documet. I order for such typig to be doe efficietly, some cosiderable traiig is required. It would, of course, be easier to write directly oto a electroic whiteboard or oto a covetioal board while someoe is holdig a camcorder. But, for those who take the trouble to acquire the skills for efficiet typig, the advatages are maifest. The documet scree allows rapid ad cotiuous scrollig so that othig has to be erased as the lecture progresses. The otes beig produced have a truly professioal textbook look. I build i several differet colored highlightig optios to make it easy for the studet to distiguish betwee differet items i the otes. The otes are easy to publish o a website ad, i order to read ad prit the otes, a studet is ot required to purchase ay software. Typig aids such as "drag ad drop" make it possible to produce otes at a vastly greater rate tha ayoe ca realize while writig o a blackboard, ad I am able to show may more workig steps. Durig the lecture, I ca retur at ay time to a positio i the documet ad isert additioal workig steps i respose to studet questios. The draggig process also provides a visual effect, allowig the studets to see where somethig comes from. I ofte begi a lecture by opeig the otes of the precedig lecture, savig it uder a ew ame, ad the workig through homework problems that were placed i that documet. This saves me the time ad effort of rewritig those homework problems. Fially, while teachig, I ca ofte make my typig eve more rapid by usig the built i computer algebra system to perform operatios o my algebraic or calculus expressios, or to draw a wide variety of graphs. Moreover, I ca isert iteractive igrediets ito my otes that allow the studet to use the computer algebra system to explore the mathematics as the otes are beig read.. A Excerpt from a Set of Lecture Notes The followig excerpt from a a set of lecture otes geerated i the classroom gives a idea of how the otes ca appear. Of course, the color highlightig 1 Scietific Notebook ad Scietific WorkPlace are trademarks of MacKicha Software Ic. ( 3

4 ad other special effects caot be show here. The otes the studets see look more attractive. The Series si x We assume that x is ay give umber ad we are goig to show that si x must always be coverget. Case 1 I the evet that si x =0the umber x have x = kπ the x =kπ ad, for each we would have must be a iteger times π. Ifwe x = kπ ad the series is just 0 si x Case We ow assume that si x 0. Sice si x = ( 1 ) (si x), ad sice we kow that 1 decreases to 0 as, all we eed to see, i order to be able to use Dirichlet s test to show that si x is coverget is that, for some costat q we have for all. Now, for each we have si x +six +si3x + +six q = si x +six +si3x + +six sixsi x +sixsi x +si3xsi x + +six si x si x 4

5 We are ow goig to use the trig idetity that says that, if α ad β are ay give umbers the cos (α β) cos (α + β) = (cos α cos β +siαsi β) (cos α cos β si α si β) = siα si β I other words, cos (α β) cos (α + β) =siα si β Usig this idetity we see that si x +six +si3x + +six = sixsi x +sixsi x +si3xsi x + +six si x si x cos x = cos 3x +cos3x cos 5x + +cos( 1)x cos (+1)x si x cos x (+1)x cos = si x 1+1 si x = 1 si x ad so, for ay give choice of x, we have the iequality si x +six +si3x + +six 1 si x ad so the covergece of the series si x follows from Dirichlet s test..3 Producig Graphics Whe I am usig my computer scree as a whiteboard as I write ito a Scietific Notebook documet, I ca produce all of the mathematical graphs directly, but there is also a eed to make drawigs of the type that oe would draw freehad o a blackboard. Agai the process requires some traiig but the effort is well worth while. Oce i a while, I eed the freedom that comes with raster style graphics ad, for this purpose, I work i a raster layer i Pait Shop Pro. However, my pricipal graphics work horse is SmartDraw 3. While teachig, I ca Alt+Tab to SmartDraw, draw a figure, copy it to the clipboard, Alt+Tab back to Scietific Notebook ad paste i less time tha I could draw the figure o a blackboard. The Copy As Picture feature of Scietific Notebook also allows me to paste mathematical symbolism ito my SmartDraw figure. Whe I eed more complicated figures, I ca cheat by makig them i advace of the lecture. The aalogue i covetioal teachig would be to walk i with the figure ad project it with a overhead projector, but my method actually imports the figure ito the otes that the studets will have i their ow computers or i their hard copy prits. Pait Shop Pro is a trademark of Jasc Software Ic. ( 3 SmartDraw is a trademark of SmartDraw.com. 5

6 .4 Recordig i the Classroom There are two software products that may be used for creatig recordigs of computer activity. These are Camtasia Studio 4 ad ScreeCorder 4 5. Each has its ow role to play. Camtasia Studio icludes a recordig utility called Camtasia Recorder that is able to record ay rectagular regio of the scree, together with all soud, ad to export the recordig as a high quality AVI file. I use this recordig utility i the classroom. It has the advatage of beig very fast ad totally reliable. I have ever experieced a crash with Camtasia Recorder. Oce the AVI file has bee made, I use the MeuMaker feature i Camtasia Studio to master a CD. Withi a few miutes, I have a CD mastered with a ice friedly welcome meu that shows liks to all of my lecture otes ad to the latest movie. The Camtasia Player is also budled ito the CD ad is used automatically to play the movie. I that way, I am assured that all studets will see exactly the same thig ad that there wo t be ay techical difficulties. Camtasia Studio also provides a Pack ad Show method of supplyig movies. This method is suitable for shorter movies (ot much more tha 30 miutes of full scree playig) ad supplies the movies as EXE files that ca be the targets of hypertext liks i ay good o-scree word processor, or i a HTML file. Oe may also choose from a variety of other file types. For example, oe may choose to export the movie as a WMV file that will play i the Widows Media Player. The quality is ot quite as good but it is still good eough if the settigs are chose carefully. Note that movies viewed with Media Player must be played full scree. It is ecessary to teach studets to switch their settigs to full scree (Alt + Eter) as the movie begis playig. The greatest weakess of the Widows Media Player is the crude facilities it offers for fast-forward ad rewid. Aother disadvatage of this method is that the istructor must devote additioal wait time for coversio of the movie, ad this wait time ca be cosiderable, especially with a slower computer. A strikig advatage of this method is that the WMV file sizes are cosiderable smaller tha the AVI file sizes. Ad fially, the WMV files are suitable for streamig ad ca be made available o a website..5 Recordig Outside of the Classroom Recordigs made i the classroom are warts ad all recordigs of the actual proceedigs of a lecture. But there is also a eed for recordigs of a much more polished ature that would be made i the privacy of a office. Such recordigs could be compaios to textbooks or supplied i their ow right. For the recordig of such movies, I recommed ScreeCorder 4. Although ScreeCorder 4 exports its video more slowly tha Camtasia Recorder, ad although Scree- Corder 4 may ot match the stability of Camtasia Recorder, there are features 4 Camtasia Studio is a trademark of the TechSmith Corporatio. ( 5 ScreeCorder 4 is a trademark of Matchware. ( 6

7 i ScreeCorder 4 that make it a sie qua o for quality recordigs doe i the office. A pricipal ad uique feature of ScreeCorder 4 is its ability to supply some editig fuctios while the actual recordig is takig place. At ay momet, the movie may be paused ad the cursor dragged back to ay chose poit to allow playig of the movie made from that poit. The, if what has bee made is ot what is wated, the cursor ca be placed before the uwated material ad the recordig process started agai. All of the movie from that poit oward will be overwritte by the ew attempt. ScreeCorder 4 also allows the project to be saved at ay time. The savig is istataeous. So oe ca re-eter the movie at ay time ad make chages by overwritig all of the movie that comes after ay chose poit. By usig ScreeCorder 4, oe may make movies that are vastly more polished tha movies that have to be made i a sigle recordig sessio. The, after the movie has bee made, oe may import it ito Camtasia Studio ad use the editig features i Camtasia Studio to delete uwated portios of the movie, isert missig material, splice movies together etc. Fially, the movie ca be preseted with either the Camtasia Pack ad Show feature, or its MeuMaker feature. For eve higher quality CDs (such as those that might be created for sale), I would use a professioal quality CD masterig utility to make my welcome scree ad the place a lik there to a Camtasia MeuMaker scree..6 Copy Protectig CDs This is a very hard problem. So far, I have ot see ay cheap solutios. Be prepared to jump through hoops ad pay big bucks. Hopefully I ll have better ews i the future. 3 Hardware Issues 3.1 Recordig Soud I order to record soud, oe eeds to have a microphoe. I do ot advocate use of a microphoe that may be built ito a laptop computer. Istead, a microphoe ca be mouted o the istructor s head. For good quality soud, the microphoe should be plugged ito a small tube preamplifier that, i tur, is plugged ito the lie-i jack of the computer. You ca expect to pay about $00 for this soud equipmet. For soud equipmet eeded to make movies, I recommed that oe visit a good music store, rather tha a computer store. Note that some of the more recet laptop computers from Dell are o loger supplied with lie-i jacks, but I have bee istructed by Dell to use the microphoe jack ad have had o problems. 7

8 3. The Need for a Good Graphics Card A computer to be used for the makig of movies should have a reasoably fast CPU. I do t kow how fast is eough but I have evidece that 1.GHz seems to be isufficiet ad that 3.0GHz is sufficiet. Above all, the computer should have a good graphics card. I ordered my preset Dell 5150 laptop with a upgraded graphics card ad this computer works well durig the recordig process. If a computer lacks sufficiet computig power to make the movies efficietly, it is ecessary to go ito the scree display settigs ad, i the Advaced meu, to disable the graphics acceleratio before recordig a movie. Failure to disable graphics acceleratio i a slow computer could cause the computer to choke while the movie is beig made. Both ScreeCorder 4 ad Camtasia Recorder offer a optio for automatic disablig of graphics acceleratio, but I prefer to do it maually. The disablig of graphics acceleratio ca cause a variety of udesirable effects ad so it is vastly more preferable to have a sufficietly powerful computer ad ot to disable graphics acceleratio. Oe may also reduce the load o the computer by reducig the color depth but, i my opiio, reductio of the color depth is very udesirable. 3.3 Mouse ad Keyboard I my opiio, uder o circumstaces should oe try to use the built i scree mouse ad keyboard of a laptop computer. For fast, efficiet, ad reliable typig, carry a covetioal mouse ad a high quality ergoomic keyboard. Never use a stadard flat keyboard. Use the same keyboard at every computer at which you work. Never type o someoe else s keyboard. 3.4 Burig CDs CD copy machies have become much more commo over the past couple of years, ad the price has dropped sharply. You ca expect to fid a ice free stadig copy machie for about $000. The simplest machies would cost less, but a really ice fast machie that would work together with your desktop computer could cost as much as $8000. The CDs themselves have become very cheap. By lookig for specials ad by bargaiig o the basis of the large umber of CDs that I buy, I have bee able to reduce the cost of CDs to a miimum. I do t bother with labels. I write the course umber ad date o the frot of each CD with a Sharpie pe. I do t bother with sleeves or jewel cases but some of my studets have their ow. Others treat my CDs more harshly, but they play well i spite of such treatmet. My departmet fids it ecessary to require studets to pay for the CD blaks that are used for my courses ad this comes to betwee $5 ad $7 per semester. I have made it clear to my studets that, if ayoe comes to me ad tells me that he or she is uable to pay the fee, the I shall willigly do so o 8

9 his or her behalf out of my ow pocket. To date, I have ot had ayoe take me up o that offer. 4 Coclusio The process of usig a computer as a whiteboard requires some hard work ad itesive traiig, ad it also requires the spedig of some moey o software ad hardware. But, for those to take the pluge, it is possible to elevate the quality of mathematics teachig to a ew level. The respose I have had from studets is ethusiastic ad they show great appreciatio for the service that I provide to them. Time ad time agai, I have heard studets complai that they felt that they uderstood the material whe they were sittig i the lecture but the they could t make sese of it later whe they were readig the otes. My movies allow them to go back to the actual lecture wheever they like ad tositthroughaypartofitthattheyeed. Ad yes, I have oticed a lower drop rate ad higher course grades. 9