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Teacher Training Workshop for Educators of Students Who Are Blind Or Low Vision Supalo et al.: Teacher Training Workshop for Educators of Students Who Are Blind or Low Vision Vol. 13, No. 1- Spring, 2009 Journal of Science Education for Students with Disabilities Teacher Training Workshop for Educators of Students Who Are ● , Danielle Dwyer, Heather, L. Eberhart, Blind or Low Vision Natasha Bunnag, Thomas E. Mallouk Cary A. Supalo, Danielle Dwyer, Heather L. Eberhart, Natasha Bunnag, and Thomas E. Mallouk Abstract: The Independent Laboratory Access for the Blind (ILAB) project has developed a suite of speech accessible tools for students who are blind or low vision to use in secondary and post- secondary science laboratory classes. The following are illustrations of experiments designed to be used by educators to introduce them to the ILAB tools, and to demonstrate how these tools can be incorporated into standard laboratory experiments. Information about the Lawrence Hall of Science’s SAVI/SELPH curriculum is also discussed. INTRODUCTION A 1993 study found that over 2/3 of graduates from the schools for the blind were unem- Residential schools for the blind have pro- ployed and a significant percentage received vided educational services to students who uncompetitive wages (6). In addition, only are blind or low vision (BLV) for well over 2.7% of the workforce in the science, technol- 100 years (1). In 1975, the passage of public ogy, engineering, and mathematics professions law 94-142 (Education of All Handicapped are physically disabled, and, of this percent- Children Act, later renamed the Individuals age, only a small number are blind (2). Provid- with Disabilities Education Act) started the ing blind and visually impaired students with trend for students who are blind to enter the the opportunity to work in a science labora- mainstream classroom (2). However, this trend tory can be advantageous to their employ- is leading to the enrollment of a larger propor- ment expectations. The provision of tools and tion of students with multiple disabilities and/ training, which can increase their self-efficacy or lower cognitive abilities in the residential with regards to the performance of laboratory schools for the blind (3). tasks, may encourage students who are BLV to pursue these lucrative professions (7). According to Omvig, the quality of education and training will decline, and the assistance WHAT ARE THE TOOLS? and support a student who is BLV initially needs will be drawn away because of the im- Submersible Audible Light Sensor (SALS) mense amounts of staff time needed to help the severely disabled (4). Day recommends The SALS is a battery-powered device that that residential schools for the blind shift registers solution color change or precipitate from a more purely academic role to an “en- formation in real time with sound (8). The abling readiness” mentality, giving students design is user-friendly, with talking controls with BLV the skills necessary to thrive in a and output, and is also cost effective (parts and sight-centered world and the ability to learn labor cost $50-100, depending on the number and develop throughout their lifetimes (5). of units produced). The SALS is based on a 9 Published by RIT Scholar Works, 2009 1 Journal of Science Education for Students with Disabilities, Vol. 13, Iss. 1 [2009], Art. 3 Teacher Training Workshop for Educators of Students Who Are Blind or Low Vision Vol. 13, No. 1- Spring, 2009 Journal of Science Education for Students with Disabilities photocell that measures light intensity chang- the conductivity probe attached to a 25 mL es. The photocell is encased in a transparent volumetric pipette, which can be immersed “wand” that is small enough to allow measure- into the separatory funnel. This apparatus was ments to be made in ordinary test tubes or developed for a biodiesel synthesis/separation beakers. The test tube or beaker is placed over experiment, which was performed by 20 high a light box or a white reflective surface such school students at the National Federation of as a piece of printer paper, as illustrated in the Blind (NFB) Youth Slam in summer 2007. Figure 1. As a reaction proceeds, the varying light intensity at the tip of the sensor wand is converted electronically to an audible tone. The chemical change (e.g., how cloudy or dark the solution becomes) is indicated by a more pronounced change in pitch, usually from high to low. The SALS control box has a memory function that allows reference and data pitches to be stored. It can output these pitches di- rectly or as spoken frequency values. FIGURE 1. Monitoring a color change in a chemical reaction using the SALS and a light box. The SALS control box can also be fitted with FIGURE 2. A simple ionic conductivity a simple conductivity probe that allows it to probe (consisting of two insulated wires, detect the conductivity difference between exposed at the tip with a gap between them) two solutions, for example, aqueous and can be used with the SALS controller box non-aqueous layers in a separatory funnel. to convert conductivity to audible pitch. This allows the student conducting an organic chemistry experiment to use the separatory Vernier Laboratory Probes and JAWS Scripts funnel, detecting the point at which the more A number of experiments have been adapted dense solution has passed completely through for students who are BLV, using the Vernier the stopcock at the bottom. Figure 2 shows Software & Technology laboratory probe 10 http://scholarworks.rit.edu/jsesd/vol13/iss1/3 2 DOI: 10.14448/jsesd.02.0002 Supalo et al.: Teacher Training Workshop for Educators of Students Who Are Blind or Low Vision Teacher Training Workshop for Educators of Students Who Are Blind or Low Vision Vol. 13, No. 1- Spring, 2009 Journal of Science Education for Students with Disabilities line in conjunction with their Logger Pro 3.5 Logger Pro also allows the space bar to start data collection software package. These have and stop data collection, which gives a student been successfully interfaced with the Job who is BLV unprecedented control over data Access with Speech (JAWS) text-to-speech collection. Once collection has concluded, screen reader package by means of the JAWS data can be exported into Microsoft Excel, al- scripting language, which is flexible enough lowing a student who is blind to eliminate bad to allow computer programmers to custom- data points and construct a best-fit line. ize JAWS for applications not envisioned by JAWS software engineers. For the first time, Vernier’s Lab Pro serves as a probe inter- this allows a screen reader to relate all data face hub and is connected to a PC via a USB displayed on Logger Pro. The Vernier probes standard cable. The Lab Pro can be powered and JAWS software may be used in conjunc- either by four AA batteries or by AC power. tion with more recent versions of Logger Pro This device contains four analog ports for the as well. Additionally, the Ohaus Scout Pro line Vernier analog probes, as well as two digital of balances is among the few types of balances sonic ports allowing the use of digital probes that are Vernier Logger Pro compatible. such as the Vernier drop counter. The Vernier temperature probe, pH probe, colorimeter, and A set of hotkeys allows students who are BLV Vernier drop counter were used in the various to listen to real-time probe readings from experiments in this training workshop. Logger Pro. The control+shift+S keystroke announces the order of the probes displayed Laboratory tools for students with BLV were on the sensor line, and corresponding real- developed in the 1970s at the Lawrence Hall time probe readings are announced by using of Science at UC-Berkeley. Their curriculum, keystrokes constructed in a similar manner: Science Activities for the Visually Impaired/ control+shift+1 announces the first probe read- Science Enrichment for Learners with Physical ings, control+shift+2 announces the second Handicaps (SAVI/SELPH) (10, 11), consists probe readings, etc. If control+shift+S an- of low- tech (and inexpensive) ways for BLV nounces temperature, pH, and conductivity, students to work with non-volatile chemicals; in that order, then control+shift+3 announces specifically, liquid measurement using notched readings for the conductivity probe (9). syringes, Braille-labeled floaters for use in conjunction with graduated cylinders, non- Another hotkey is control+shift+A, which traditional metal thermometers that allow for announces all objects on the screen. This Braille labels, and easy bench-top organiza- includes descriptions of X-Y Cartesian graphs, tional methods are stressed. One technique is real-time probe readings (both digital and the utilization of a standard cafeteria tray to be analog), and access to the data table. All are used in the work space of the student who is accessible with the control+tab keystroke. BLV. All glassware needed for the experiment When the table is selected, the up, down, left, can be placed on the serving tray by the teach- and right arrows navigate columns and rows er in advance of the lab period starting. This of the data table, which are read along with the helps students who are BLV to know exactly data displayed at that data point (9). where glassware and other essential equipment 11 Published by RIT Scholar Works, 2009 3 Journal of Science Education for Students with Disabilities, Vol. 13, Iss. 1 [2009], Art. 3 Teacher Training Workshop for Educators of Students Who Are Blind or Low Vision Vol. 13, No. 1- Spring, 2009 Journal of Science Education for Students with Disabilities are located and minimize possible accidents. It of transmittance and amount of absorbance. also doubles as a spill tray to minimize chemi- The colorimeter is an analog probe device that cal spills in the work space.
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