Problems with True and False Tests

Teachers should know how to write and grade tests. Regrettably, they don't always use good assessment methods. 

True/False Tests and Guessing

Please answer the following true/false item:

___T ___F   Neils Bohr accepted the principal of complementarity as a necessary part of quantum theory.

If you actually participated in my one-question true/false "test" you had about a 50-50 chance of getting it right (unless you are quite knowledgeable regarding quantum theory). The question was easy for me to write-- I modified a phrase from a website. 

True/false tests have perhaps two advantages over other types of tests: (1) they are quickly written, and (2) they are quickly scored. 

These two advantages are both for the convenience of the teacher and do not offer students much. The trap for both students and teachers lies in the 50-50 chance of a correct or wrong answer. This encourages guessing-- not a test-taking skill to be encouraged. Also, because true/false items generally address simple concepts a large number of them is necessary to produce valid results. 

The chance factor is also important in scoring. Teachers typically grade them as they do other test items-- i.e., 20 items will count 5 points each (100% / 20 = 5). Thus a student who misses 10 of 20 will receive a score of 50. But if the items are fairly written a chimpanzee  trained to use a pencil could be expected to get half (10) of the items correct. Did the chimp know the answers? Likely not. Should the chimp receive 50 points based on chance? Well, if the teacher wants to grade according to knowledge the answer would be "No."

The correct way to grade true/false test and score for the "guess factor" is to multiply misses by two (the number of choices) and subtracting the result from the percent right. Each item counts 5 in a 20-question test. 

"Traditional" scoring simply deducts 5 points for each one missed:

100% - (5 X 10) = 50%

Scoring to compensate for guessing is different (and correct):

10 right X 5 = 50%;

10 wrong X 5 = 50%;
% right - % wrong + 50% - 50% = 0

Another view of the same "correction score" method is:

100% - two times the percent wrong;

100% - 2(50%) = 0

Students who score around 50% with traditional scoring techniques are demonstrating a score predicted by guessing! Of course, the same issue arises with any multiple choice test. After all, a true false test is a multiple choice test with 2 choices. The effect of guessing is reduced as more choices are added. 

Do True/False Tests have Value in Real Assessment?

The short answer is "Yes." But if a they must be used, consider them for formative (ungraded) activities designed for teaching simple concepts and adding variety to instructional methods. True/false worksheets can be an good exercise for homework.

True/false tests can be improved by having students justify their answers, but why not simply ask a short-answer question to begin with? 

By the way, the sample item at the beginning is "true."

Does Your School Add to Teacher Stress by Wasting Instructional Time?

Teacher stress is increased by wasted time.

There is no doubt that many school principals have mastered the ability to establish priorities in schools. Some principals are victims of the various demands of the school. This may be especially true when a principal is new to a school that has established practices that waste time.

Other practices that waste time that are often simply accepted are:

• No policy on announcements which may interrupt a class at any time.
• Rewarding students for various achievements — like excelling in a fundraiser — with time out of class.
• Standardized testing and excessive preparation for the tests.
• Inefficient procedures for starting the school year.
• Inefficient procedures for ending the school year.
• Being involved in too many different well-intended programs.
• Early dismissals for sports and other activities.
• Overloading teachers with secretarial tasks.
• Too many emails that require immediate attention or personal emails among the faculty.
• Gearing down for holidays, especially Christmas.
• Excessive reliance on videos as teaching tools.
• Excessive reliance on homework, correcting it, and recording the grades.
• Grading too much student work of all kinds.
• Days of recognition for “special occasions or people” legislated by different states.
• Frequent problems with heating and/or cooling systems.
• Classes that are too large to allow individual attention.
• Teachers who are absent excessively.
• Useless appointments to serve on committees.
• Covering another teacher's class due to substitute shortage.

GRADING AND REPORTING STUDENT LEARNING

Grades are "not essential to the
 instructional process."

General Conclusions From the Research:

1. Grading and reporting are not essential to the instructional process.

2. Grading and reporting serve a variety of purposes, but no  one method serves all purposes well.

3. Grading and reporting will always involve some degree of subjectivity.

4. Mathematic precision does not yield fairer or more  objective grading.

5. Grades have some value as a reward, but no value as a punishment.                    

6. Grading and reporting should always be done in reference to learning criteria, never "on the curve."

7. Three general types of learning criteria are used in grading  and reporting:    
 a. Product criteria
 b. Process criteria
 c. Progress criteria
8. Report cards are but one way to communicate with parents.
    
    Guidelines for Better Practice:
1. Begin with a clear statement of purpose and specific learning goals.
    a. Why are grading and reporting done?
    b. For whom is the information intended?
    c. What are the desired results?
2. Ensure that grading and reporting methods provide accurate and understandable
    descriptions students learning.
    a. More a challenge in clear thinking and effective communication
    b. Less an exercise in quantifying achievement
3. Use grading and reporting methods to enhance teaching and learning.
    a. Facilitate communication between teachers, students, parents, and others.
    b. Ensure that efforts to help students are consistent and harmonious
4. Alleviate questionable practices:
    a. Example 1: Averaging to obtain a student's grade or mark.
    b. Example 2: Assigning a 'zero' to work that is late, missed, or neglected.
    c. Example 3: Taking credit away from students for behavioral infractions.



From: Guskey, T. R., & Bailey, J. M. (2001). Developing Grading and Reporting
Systems for Student Learning. Thousand Oaks, CA: Corwin Press.
Guskey, T. R. (2002). How’s My Kid Doing: A Parent’s Guide to Grades,
Marks, & Report Cards. San Francisco, CA: Jossey-Bass.

Grades have no value as punishment.