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Display in the classroom

  • 1.  Display in the classroom

    Posted 09-27-2018 09:34
    Are you currently using projectors or interactive projectors in the classrooms or have you replaced those with interactive flat panels (interactive TV units) and if so, what diagonal size have you selected? Above all, have you selected the diagonal size according to your classroom size and the view area for the students? We have old Promethean units with projectors that are due for replacement and we are considering moving to interactive TV displays, but we are evaluating the actual diagonal size provided by different interactive TV vs interactive projector. Thank you,

    Fernando De Velasco
    Chief Technology Officer
    Prosper ISD
    Prosper TX

  • 2.  RE: Display in the classroom

    Posted 09-28-2018 07:26
    We are in the process of replacing many of our traditional projector base, touch interactive systems (e.g., SmartBoards) with non touch interactive consumer grade flat panel units.  We are starting at our high and middle schools and exempting math and some science classrooms, who rely on the touch interactivity of the older units.

    We chose 65" displays because they were the largest we could find that were still proportionately priced.  We found units for approximately $500, plus mounts and HDMI cables.  We priced commercial grade units, which have some compelling features, but found the price differential to be prohibitive.

    Also, note we've had issues with 50 foot HDMI cables as they connect via dongles to Dell docking stations.  Nearly all of these issues have been resolved with shorter cables and/or installing new drivers for the docking stations.  Make sure to test many different cables, dongles and docking stations to determine compatibility rates.

    We are also reviewing forms of interactivity that don't rely on touch sensitive screens, such as annotation software that runs on tablets.

     We saw inconsistent utilization of the touch interactivity and sought to provide a more cost effective solution for the majority of teachers who don't use touch interactivity.  So far, the embrace has been positive, as the images are far crisper than the projector images, even when considering there is less "real estate" on the displays than on the projector screens.

    Todd Jones
    Chief of Technology
    Orange County Schools
    Hillsborough NC
    (919) 245-4100 (15001)

  • 3.  RE: Display in the classroom

    Posted 10-01-2018 10:14
    We are replacing our failing interactive displays with Sharp commercial grade 70" or 80" (depending on classroom size) non-touch displays as well. Most of the displays are mounted on a cart, giving the teacher some options to move the display around the classroom and accommodating flexible seating and small group instruction. We are making the switch to non-touch displays for several reasons.

    1. Cost. With budgets tightening and large numbers of aging displays failing at once, I can't afford to put a large touchscreen display in each classroom that needs it. The non-touch commercial displays are only costing about half the price of an interactive display of the same size (that includes assembly and installation).

    2. Usage. We, too, found that most classrooms were using the interactive panel as a projector. In most cases, if anyone touched the display, it was the teacher only.

    3. Pedagogy. With one interactive display in the room, this means only the teacher (or at best a handful of students at a time with more modern touchscreen displays) are interacting with the content at a time. When all of our students have a touchscreen device in their hands, I have a hard time accepting that the teacher should be front and center and choosing students who can interact with the content. All students in the room should be engaged in manipulating the content and taking part in the instruction.

    While our teachers have had some reservations about the change, it has gone pretty smoothly.  Here are a few resources my tech coordinator has made that explain how we're making this work in the classroom. 

    If I could afford it, I would probably buy the interactive displays. I'd buy 2-3 per room so small groups could work around them. However, this non-touch option is working out for us, and our teachers are adapting.

    Sharp has been easy to work with, excellent on pricing, and they assemble the carts or mount the tvs for us on site. We've had displays installed over the summer, but also last winter while school was in session. I highly recommend them!

    Chantell Manahan
    Director of Technology
    MSD of Steuben County
    400 S Martha Street
    Angola, IN 46703
    (260) 665-2854
    Twitter @leadlaughlearn

  • 4.  RE: Display in the classroom

    Posted 09-28-2018 08:19
    70-80" Sharp interactive TV's. We've been using them for seven years now. Love them. We started out with 70", but have gone larger based on classroom size and price (we get the 80" now for what we paid on the 70" 6-7 years ago).

    Ryan Bennett, CETL
    Director of Technology, Peddie School

  • 5.  RE: Display in the classroom

    Posted 09-28-2018 09:05
    We have been using Interactive Projectors because it is difficult to meet the InfoComm size recommendations in our larger classrooms without using a projector.

    Chris Whitman
    IT Director
    Bloomer School District
    Bloomer WI
    (715) 658-2800 (1360)

  • 6.  RE: Display in the classroom

    Posted 09-28-2018 09:12

    We have standardized on 75" interactive panels to replace our projectors.  In the secondary schools we are using the balance box to allow teachers to raise the panel for students to see in the back of the room.  We still use projectors in large spaces. 


    David Spann
    CIO, McKinney ISD

    Phone:  469-302-4081 | Fax:  469-302-2830 | | 

    #1 Duvall McKinney, Texas 75069



  • 7.  RE: Display in the classroom

    Posted 09-28-2018 09:24
    Edited by Jaime Kikpole 09-28-2018 09:26
    Todd Jones:  So you're using run-of-the-mill TVs?  And starting by replacing the interactive projectors/displays in the very rooms that most like them?  I've very curious how that is working out.  Would you be willing to share more?

    Chris Whitman:  Can you share the InfoComm size recommendations that you referenced?  They sound very useful.

    All:  Are you removing the dry-erase whiteboards and/or chalkboards as you make these changes?  In our buildings, those are far larger than a 65" or even 80" display or a 100" projection area.  My teachers are making the valid point that this would be a reduction in service level for basic uses.

    Jaime Kikpole
    Director of Technology and Innovations
    Cairo-Durham CSD
    Cairo, NY
    (518) 622-8543 x59500

  • 8.  RE: Display in the classroom

    Posted 10-01-2018 07:12
    Todd Jones:  So you're using run-of-the-mill TVs?  And starting by replacing the interactive projectors/displays in the very rooms that most like them?  I've very curious how that is working out.  Would you be willing to share more?

    Mr. Kikpole: Yes, we're using 65" consumer grade displays we found for $500 a unit.  We looked at other options and found commercial grade units far more expensive.  We've run into some issues with long HDMI cable lengths (50' plus DisplayPort adapters coming from Dell docking stations), but we're working through those with shorter cables and/or direct connect to laptops.

    Of course, older SmartPhones can download TV remote control apps, which allow some classroom mischief, but teachers figure that out pretty quickly.

    The general consensus is that they're a big improvement over our aging fleet of projector based SmartBoards.  Given the low levels of touch interactivity we've seen in our classrooms over the years, we thought it was imprudent to invest in screen based interactivity across the board.  We're also looking into different forms of interactivity, like annotations through tablets, or tokens that allow a student device to display on the screen, or on a sub-group of other student devices.

    The cost savings is, of course, immense.  Up to $10,000 for one of the interactive Smart flat panel displays vs. $500 (add another $60 for mount and cabling) and we shrink the number of classrooms needing screen interactivity to a very manageable few.

    Let me know if you have other questions.

    Todd Jones
    Chief of Technology
    Orange County Schools
    Hillsborough NC
    (919) 245-4100 (15001)

  • 9.  RE: Display in the classroom

    Posted 09-28-2018 09:51
    Hello Fernando

    It has been a while since we last spoke. I hope you are doing well.

    Display Image Size for Instructional Content in Classroom Audiovisual Systems.

    In audio visual (AV) installations, the common standard used for determining screen size known as the 4/6/8 rule. This rule establishes that ideal viewing distance, in correlation with room size, should be four, six or eight times the height of the screen for analytical viewing (AV), basic viewing (BV) and passive viewing (PV). The advantage of applying this rule in classrooms is that the distances can be measured according to particular activities needing use of the screen.

    By that rule, selecting the display as either basic viewing (BV) or analytical viewing (AV). In BV scenarios, you would divide the distance to the furthest viewer by six to calculate image size. In AV situations, divide by four.

    The common use for screens was for basic instruction viewing instructional software content. For these uses, most applications were considered BV. AV was used for critical uses such as medical, engineering and occasionally for instruction. Under the old standard, the following common instructional spaces and average viewing distances yielded these common size outcomes.

    Screens size when using 4-6-8 Rule

    Instructional Space           Furthest Student              BV                               AV

    Classroom                                    25'                    91" Diagonal                  72.5" x 116"

    Training Room                            35'                    133" Diagonal                 100" x 160"

     Past classroom designs selected SVGA 800x600 or XVGA 1024x768 resolutions for display presentation (introduced in 1990). Teachers gave traditional presentations which looked acceptable. As times changed, sources and displays/projectors improved their resolutions, and presentations started using higher quality source materials.

     The Infocomm DISCAS standard for image size determination considers the improved resolution of projectors and the impact higher resolution projectors and content has on the ability for viewers to see and understand the content. The standard incorporates several factors not previously considered, though DISCAS still has basic decision making and analytical decision-making guidelines.

     For this example, HD or 1920x1080 (introduced in 2011) resolutions are assumed as the consumer industry has set this as the current baseline for our available product mix. The share of these higher resolution sources and displays/projectors have become common in classrooms. In BV guidelines, a font size is also factored. For our purposes, a 20 PT Font is used as a typical element in a presentation. Using DISCAS BV, 1080 lines and 20 PT Font, the recommendation for image size to furthest viewer is a factor of 5.

     DISCAS yields more recommendations for larger screens than previously suggested. With the BV standard using a divisor of five instead of six, screens need to be 16% larger. Students expect better presentations full of video and high-quality imagery. This is true in all instructional spaces. Under AV guidelines even larger screens are needed. Screens likely to be specified when DISCAS is considered

     Screens size when using 3-5-7 Rule

    Instructional Space           Furthest Student              BDM                            ADM

    Classroom Room                         25'                    110" Diagonal                 87" x 139"

    Training Room                             35'                    159" Diagonal                120" x 192"

    This workup is for HD or 1920x1080, the required diagonal screen size for instructional spaces will increase as the sources and displays/projectors increase their digital resolution capacity i.e., 4K 2160x3840.

     I have included the link to calculating Display Image Size for 2D Content in Audiovisual Systems

     And the Epson calculator

     AVIXA Display Image Size for 2D Content Standard, for those that want to read the standard.

    Joe Sanders, ALEP, CETL
    512 484 6930

  • 10.  RE: Display in the classroom

    Posted 10-01-2018 09:25
    Hello Joe,

    Great to hear from you. We measured our rooms both where students sit directly straight and the furthest diagonally across the room in relationship to the display. We also considered our old 78" Promethean boards (4:3 ratio though, which no longer applies with all other components being 16:9/10 that now produce an image similar to a 75") and our current Epson interactive with their whiteboards capable of 90". We put side by side 65~86 TV units against projectors for sharpness, clarity, etc. In addition to that, while Chromebooks have brought the content straight in front of the students (different teaching model), we still need a good size display (considering any student with eyesight problems) to show content and follow along without putting any strain on the student side. With all that (and a few other things we have found out and are considering), we see a +80" the required in our environment (emphasis in "our" as I understand everybody has different scenarios and constraints). The main issue with larger units is the cost of course, but at this moment we have Epson interactive+whiteboard vs an 86" close enough to start budgeting that direction. I hope all is well. Regards,

    Fernando De Velasco
    Chief Technology Officer
    Prosper ISD
    Prosper TX

  • 11.  RE: Display in the classroom

    Posted 09-28-2018 10:09

    Within the last year, we have started used Promethean AP6-70 interactive panels in the classroom. We went back and forth between 70" and 75" but decided on 70" because of a significant cost difference. We also put them on carts so they can be moved closer to students or setup for a group participation.
    Our sales rep indicated the size would be appropriate for 30 or less students and/or 30' x 30' size classroom. So far teachers and students are loving them and I have not heard of any size issues. I assume you can always move students around if they have issues seeing the panel.

    Tom Hering
    Director of Information Technology
    North Central Region (META)
    Great Falls MT
    (406) 268-6068