CBA Tricks of the Trade
This section and the next, Effective Personal Strategies, present various ideas which, while they are not necessary to the functioning of CBA, are nonetheless very useful. The distinction is that the suggestions in this section are not a matter of opinion, while those in the next section are. Hence the title: Effective Personal Strategies.
Link transfers:
First, the term "link", when used with respect to TI calculators, means simply to transfer program or data from one calculator to another. It has no connection to the linking concepts associated with program compiling in the computer world at large.
The most common reason for failure of the link process for passing a program to a calculator is simply a failure to push the link cable connector all the way home. There is one last 1/16th of an inch in which there is something like a "snap".
The second most common reason for failure of the link process is a matter of timing. The screen of the receiving calculator must say WAITING prior to pressing [ENTER] to transmit on the transmitting calculator.
The reason for a consistent repeated failure to receive or transmit from a given calculator when other calculators and cables work well is an unfortunate weakness in the TI-83. The link connector can fail, even if it is not abused. While it is sometimes possible to make repairs, it was not designed to be repaired, and repair is not recommended. TI has been very good about honoring warranty claims with regard to this defect.
The great advantage of the TI-83 Plus over its earlier cousin, the TI-83, is that the Plus can store the entire CBA course, eliminating the necessity to do daily, or even weekly linking of programs. The downside is that, as the archive of the Plus becomes full, the program selection and linking time can become very long. Given that you have the option, there is an advantage to using the earlier TI-83 when you are linking a smaller number of programs between calculators.
When making repeated links, as for example, when setting up an entire classroom set, or when students are daisy-chaining a program from one to another, do not quit out of the link function. The programs selected for linking will remain selected as long as you do not quit out of the function. Unfortunately, if the transmission fails, then you have no choice but to quit out of the function, and you will have to reselect the programs to be transferred.
Programs can be transferred from one TI-83 Plus to another without taking them out of archive. An archived program on the transmitter will result in an archived program on the receiver. All programs linked to a Plus from a computer via GraphLink will reside in RAM (unarchived) on the receiving calculator.
While the Ti-83 Plus has functions under [2nd] [MEM] called Archive and Unarchive, it is generally much more convenient to use the second function on the same screen called 2:Mem Mgmt/Del. Under this function, any selected program can easily be toggled between archive and RAM by simply pressing [ENTER].
Selecting a program:
The time for the initial logo screen can be shortened by pressing any key while the logo is being displayed.
After exiting from any program, the easiest way to re-enter the program is simply to press [ENTER]. To re-enter some previously executed program, one can press [2nd] [ENTRY] repeatedly to call up the required command. Because of the slowness of a fully loaded Plus in selecting a program, this may become a preferred approach to program selection.
Even in selecting a program which has not been used in the past, it sometimes advantageous to use the [2nd] [ENTRY} approach and then simply overtype the program name. This is especially true if the names are as similar as Eqn1Stp1 and Eqn1Stp2.
The [2nd] [ENTRY] function can also be very useful if you find it advisable to review what student has been doing.
In selecting a program near the end of the alphabetical list, it is frequently an advantage to press the up arrow and use the wrap-around reverse-scroll facility that is provided.
Response entry:
Students are usually not aware that over-typing can take the place of deletion. It is also not necessary to move the cursor to the end of a corrected entry before pressing [ENTER]. What you see is what you get.
In correcting errors in long entries, quadratic formula answers, for instance, it is helpful to be familiar with the [2nd] [INS] facility to insert characters into an existing line.
Many of the programs require that the answer be in the form of a complete equation or inequality. The symbols =, <, > are found at [2nd] [TEST].
Exiting the program:
If the goal is simply to break out of the program, you can press [ON]. However, it is much preferable to press [ALPHA] [E] at some point when the program is asking for input, because this performs a graceful exit and leaves the calculator mode in a standard state (Full screen, floating decimal etc.). It also causes a display of the Performance Summary screen with the results of the student's efforts at that point.
Restarting a program:
Restarting a program from a point other than the beginning can be useful in a number of scenarios. The procedure is described under Error Recovery. When a program is restarted at a problem number which is some multiple of four plus one, then the full set of four problem types will be presented in order, without randomization. The randomization occurs after the number of problems executed reaches a multiple of four.
Checking on last input:
It sometimes is the case that a student will insist that an answer, which was previously rejected as incorrect, is now accepted as correct. The calculator is not capable of doing such a thing, but the student may be hard to convince. If you exit the program, you can use the AA program to view the most recent input and the last four erroneous inputs for the current program. If AA is not on the calculator, the same thing can be accomplished by using the [VARS] [7] sequence to examine the contents of Str1, which will be the most recent input, and Str0, Str9, Str8, and Str7, which are the preceding four erroneous inputs, working back in that order. This will usually reveal the errors that were made. Of course the program can then be restarted as described under Error Recovery.
Student numbers
The programs require that a three-digit student number be entered. A convenient way to assign these numbers is to let the first digit reflect the period and the next two reflect the seat number. For example, the student who is assigned to seat number 5 during second period would have student number 205. He would be assigned (and be responsible for) calculator number 5. When he presents his calculator for grade recording, the calculator number, his seat number, and the number on the Performance Summary screen should all match. It is only on rare occasions that this would be an issue.
Even the teacher must use a number. You may find it convenient to use the same number, always, for example, 888.