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Researching Achievement


Summary table of sound enhancement efficacy studies demonstrating student improvement in literacy and academic achievement

Table data taken directly from Sound Field Amplification: Applications to Speech Perception and Classroom Acoustics (Second Edition) by Carl C. Crandell, Joseph J. Smaldino, and Carol Flexer.

Investigators Student Population Improvement in Academic Achievement
Obtained with SES*'s
Sarff (1981); Ray, Sarff, & Glassford (1984) MARRS project (fourth-through sixth grade students with minimal hearing loss, academic deficit, and normal learning potential) The MARRS project demonstrated that students with minimal hearing loss and learning disabilities in amplified classrooms made significant academic gains at a faster rate, to a higher level, and at one-tenth the cost of students in unamplified classrooms and receiving traditional pull-out resource-room intervention.
Ray (1992) MARRS validation (fourth through sixth graders with minimal hearing loss and academic deficit.) Students with minimal hearing loss instructed in unamplified classrooms performed academically at an average .4 SD below normal. Students with minimal hearing loss in amplified classrooms performed at or above average.
Flexer (1989, 1992); Osborn, VonderEmbse & Graves (1989) MARCS project (kindergarten through third graders in regular education classes) Students in classes with FM sound field amplification achieved higher scores in listening, vocabulary, math concepts, and math computation on the Iowa Test of Basic Skills, with greater gains made by younger students.
Schermer (1991) First-grade students with normal hearing and minimal hearing loss Higher reading test scores were attained by students with minimal to mild hearing loss in amplified classrooms, and decreased post test scores were identified for students with known minimal to mild hearing loss in unamplified classrooms.
Howell (1996) 15 normal-hearing, regular education 3 graders Significant improvement was noted in test scores when teacher used sound field FM to present new information.
Darai (2000) First-grade students (85 experimental, 81 control) in eight regular education classrooms Students in amplified classrooms achieved greater literacy gains than control students, particularly bilingual and special education students, on the Informal reading Inventory. Teachers noted positive change on the LIFE due to FM SES*.
Long & Flexer (2001) 37 kindergarten through 5th grade regular education classrooms Referral rates for special education decreased from 7.72% to 4.6% after 37 classrooms were amplified with sound field technology.
Flexer, Biley, Hinkley, Harkema, & Holcomb (2002) 53 students in 3 pre-kindergarten and 3 kindergarten classes Results revealed a trend toward enhanced development of phonemic awareness skills when phonemic awareness instruction was augmented with SES*. The least number of at-risk readers were found in the amplified preschool and kindergarten classrooms. Read more detail about this study...
McCarty & Gertel (2003) Fifth grade high need students in regular classes SAT scores improved +12% to +20% for reading, math, language, science, and social studies with a +14% improvement in total test battery in the first year, followed in second year by an average 10% improvement over first-year results.
Loven, Fisk, & Johnson (2003) 48 students in 2 regular education second-grade classes Three appraisals of academic achievement over a six-month period showed significantly better performance on reading and spelling for students in the amplified classroom but no significant differences for mathematics.

Additional Studies and Statistics on Achievement:

Boggs & McClanahan, Anaheim Public Schools, California, 2004

California - Multiple year study of 3rd and 4th grade student cohorts reported up to 15% gains in reading, math, language and spelling over a 3-year period as measured with Stanford-9.

Edwards, Office of Student Services, Oakland ISD Sound Field Report, 2003

Michigan – Secondary students showed 10% gains after four years of data collection. 75% of all classrooms are now sound enhanced in the intermediate school district.

Florida Secondary Schools Student Achievement in Sound Enhanced Classrooms

  • 3-year historical gains study reported improved student achievement with 6th–7th–8th grade students.
  • 10-11% minimum gain as measured by FCAT.

Effect Teacher Voice Enhancement Had on High Achieving Schools

JEFFCO Public Schools – Golden, Colorado - Maple Grove Elementary

  • Previously scored in 8th and 9th Stanines
  • Assessments increased average of 3.6% after implementation of SES* and continued over three year study, 2000-04. This is statistically significant given the fact that these students were already "high-achievers" and did not have a lot of room for test score improvement.
  • Earned "John Irwin School of Excellence"

5th Grade SAT Student Gains Pioneer Elementary – Salt Lake County, Utah

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Orange Co. PS (Ivey Lane Elem.) Reverse Failing Scores (Grades 3 & 4)with Florida’s FCAT tests

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Summary of 2006 Australian Study:
The Impact of Sound Field Amplification in Mainstream Cross-Cultural Classrooms

Part 1 Educational Outcomes by Robyn Massie and Harvey Dillon
As published in the Australian Journal of Education, 50(1):62-77

The aim of this study was to examine the effects of sound-field amplification intervention on the acquisition of specific educational goals for children in mainstream cross-cultural classrooms. Twelve classes of Grade 2 children participated in the project. For classes 1-8, the listening environments were alternated between amplified and unamplified conditions, each condition being for two terms (one semester) of the school year. Beneficial effects of amplification were obtained in all three skill areas of reading, writing and numeracy. The beneficial effects occurred irrespective of whether the children had English as a native language or had English as a second language. Classes 9-12 were alternated between single-channel and dual-channel transmission options, each condition being for one semester of the school year. The results indicated using different numbers of microphones did not affect the rate of acquisition of educational outcomes
. Read more detail about this study...


* SES = Sound Enhancement System