Tennessee Value-Added Assessment System
The Tennessee Value-Added
Assessment System (TVAAS) is unlike any other state-wide accountability program. Instead
of ranking schools by how their students score on a standardized test, it provides
information to teachers, parents and the public on how schools are doing in helping each
child make academic gains each year. It provides information to school administrators
to identify weaknesses in even the strongest schools. And it provides
information to central administrators, school boards and policy leaders to
ask harder, more penetrating questions.
How well does it work?
Well enough that in a report by the Council of
Chief State School Officers, Tennessee's 8% increase in math and science scores was linked
to TVAAS. "[Tennessee] has a very innovative assessment system," said Lary
Suter, head of research and development for the National Science Foundation, which funded
the CCSSO's research. "It has detailed information for how students change from grade
to grade and they've been able to relay that to their teaching practices. It's been
exceedingly well done."
In addition, Tennessee is one of the few states that have
shown improvement on the National Assessment of Education Progress since TVAAS was
implemented in 1992.
So what is TVAAS anyway?
TVAAS is, at heart, a statistical methodology. It is a system
that begins with testing each student in each grade in a number of subjects. Through 1997,
Tennessee tested second through eighth grades in Reading, Math, Language, Science, and
Social Studies using the CTBS/4 test by CTB/McGraw Hill. Since 1998, the Terra Nova test from the same
company has been used in grades three through eight.. Any number
of tests, both commercially developed and developed by individual states, could be the
basis for Value-Added Analysis. Value-Added Analysis is what is done with the results of
Quite simply (although the math is
complex), Value-Added Analysis takes the gains each student makes from year to year and
compares it to the gains made by a normative sample for that same subject between those
same grades. Thus, if the normal gain from 4th to 5th grade in math
was 15 points, a 5th grade teacher's students who averaged a 15 point gain for
the year would score "100", or 100% or normal gains. A teacher whose students
averaged an 18 point gain would score 120, and so forth.
How has TVAAS been received by teachers and administrators?
With great suspicion at first. But, it was part of a package
that included a one-half cent increase in the sales tax rate in Tennessee, earmarked for
schools. So they went along. Now teachers and administrators across the state are finding they can actually use TVAAS to improve
teaching, something that no other accountability system has afforded.
What have we learned from TVAAS.
Some amazing things, really. Including:
- The effectiveness of a school in helping students make
gains cannot be predicted based on its racial or economic makeup.
- There are HUGE variations in the effectiveness of
- Our schools are getting steadily better. Fewer are to be
found with overall gains less than 70% of the national norm, and more and more are
- Students from the top quartile on TCAP
in the sixth grade can, when they get to high school, average anywhere from a 19 to a 26 on their ACT math scores
depending on which school system they attend. And, the variations correlate with the
effectiveness scores of that system's high school math teachers. Since a 26
indicates a student with a 50-50 chance
at a B or better in engineering school college calculus, this difference is
- 4th grade students in the bottom quartile
had a 62% chance of passing the math portion of our old high school
competency test if they had four straight years of the most effective
math teachers in grades 5-8, but only a 16% chance if they had four
straight years of the least effective.
- Three straight years of 5th quintile
teachers from 3rd through 5th grades result in math scores averaging
the 85th to 95th percentile. Three straight years of the least
effective (1st quintile) teachers result in scores from the 35th to
- High achieving students are the most underserved of all
- Black high achieving students are even more underserved
- High achieving students gain little or nothing during years
when they are with a 1st, 2nd, or 3rd quintile
- In a study of two of our metropolitan school systems, both
managed to increase the achievement of their lowest scoring students. But one did it at
the expense of gains for their high achievers, while the other managed to move all groups
up in gains.
I've gathered a good deal of information about
value-added analysis on this site. If you need more,
Dr. William Sanders,
School, SAS Campus Drive Bldg S, Cary,