Evaluation of Low-threshold Programming Learning Environments for

the Blind and Partially Sighted

Shirin Riazy

, Sabrina Inez Weller

and Katharina Simbeck

HTW Berlin, Germany

BIBB, Bonn, Germany

Keywords:

Educational Programming Language, MINT, Teaching for the Visually Impaired, Scratch.

Abstract:

Approximately 1.3 billion people worldwide live with visual impairments and are therefore dependent on the

use of aids. With regard to the acute shortage of skilled workers in the IT sector, the question arises as to the

extent to which people with visual impairments can enter the IT professions. While web-based programming

environments have been used to introduce children to programming, their accessibility for the blind and visu-

ally impaired is questionable. This report introduces 17 web-based programming learning environments and

examines their usability for blind and visually impaired people. In total, none of the 17 graphical programming

environments were suitable for the usage by blind and visually impaired people.

1 INTRODUCTION

Worldwide there are approximately 1.3 billion people

living with visual impairments, 36 million of whom

are blind (WHO, 2019). At the end of 2017, around

7.8 million people with severe disabilities were liv-

ing in Germany. Compared to the population as a

whole, this was equivalent to approximately 1 in ev-

ery 11 German citizens being severely disabled (9.4

percent). Blind and partially sighted people com-

prised just under 5% of all people with a severe dis-

ability in 2017 (Destatis, 2017)

. While almost 21%

of these suffered from blindness or the loss of both

eyes, just under 14% suffered from severe visual im-

pairment. Almost 66% had another form of partial

sightedness. As we grow older, the risk of losing our

sight increases. More than half of the blind and par-

tially sighted in Germany are 75 years old. General

illnesses are the most frequent cause of sight loss or

partial sightedness, accounting for 90% of all cases.

In only just under 3% of cases, those affected were

blind or partially sighted at birth. Around 25% of all

blind and partially sighted people also suffer from im-

paired functionality of internal organs or organ sys-

tems. With the number of blind and partially sighted

people having fallen over the last 25 years, a study

Between 2007 and 2017, the total number of blind or

partially sighted people in Germany rose by almost one per-

centage point.

now suggests the ﬁgure is set to rise in future. In fact,

the proportion of those affected is set to rise by almost

6 percent by 2020 (Ackland et al., 2017). According

to this study, the anticipated increase in diabetes cases

and the ageing population is likely to cause increased

eye disease and visual problems (IAPB, 2018).

In recent years there has been a substantial in-

crease in the employment rate of people with a dis-

ability (Aktion Mensch, 2019). However, people with

a severe disability state in surveys that the work de-

mands placed on them are too high and that they per-

ceive progression opportunities as poorer compared

to those of people without a disability. Just under one

third of blind people and people with severe visual

impairment of employable age are actually in employ-

ment. Previous studies have shown that blind people

and people with severe visual impairment

are par-

ticularly disadvantaged in the job market (Lauenstein

et al., 1997; Schr

oder, 1997). This is due on the one

hand to the limited range of activities as a result of

the disability. In addition, a large number of typical

The generic term ”visual impairment” is often used to

describe blindness and partial sightedness. Under German

social legislation, anybody with vision of less than 2% in

their better eye is regarded as blind. For people with severe

visual impairment, their vision is reduced to between 2 and

5% of the norm. Those affected can be treated the same

way as the blind people. For the partially sighted vision in

the better eye —despite the visual aids such as glasses or

contact lenses—is a maximum of 30%.

366

Riazy, S., Weller, S. and Simbeck, K.

Evaluation of Low-threshold Programming Learning Environments for the Blind and Partially Sighted.

DOI: 10.5220/0009448603660373

In Proceedings of the 12th International Conference on Computer Supported Education (CSEDU 2020) - Volume 2, pages 366-373

ISBN: 978-989-758-417-6

“professions for the blind” such as telephonist, mas-

sage therapist, balneotherapist, and shorthand typist

have in some cases become obsolete and in others

more complex. However, new professional opportu-

nities for the blind and the severely visually impaired

have also emerged

. This is particularly the case for

people with sight loss and partial sightedness who are

skilled IT workers (e.g. in the areas of application

development and system integration) and information

technology specialists in the area of database devel-

opment, for whom opportunities on the labour mar-

ket have been very good over the last 10 years. The

placement rate in this area of supported vocational ed-

ucation and training is almost 80%. Besides the good

opportunities on the labour market and attractive re-

muneration for the partially sighted, the IT sector rep-

resents an interesting area of work not least due to the

anticipated levels of accessibility. Many of those af-

fected who opt to train or study in this area see it as

their social duty to play a part themselves in creating

and advancing digital accessibility. Another reason

why people with sight loss and the partially sighted

often opt for the IT sector is that, due to their limi-

tations, those affected are more frequently forced to

deal with digital technologies. For this reason, when

dealing with digital technologies they very quickly

develop a natural acceptance and greater competence.

The dividing line when dealing with the medium of

the PC is not between the sighted and the partially

sighted, but instead between the partially sighted and

the blind. While the partially sighted use technolo-

gies such as the Microsoft magniﬁer which gener-

ally allows them to work in the way sighted people

work, these tools do not function for people with a

severe visual impairment or sight loss. Screen read-

ers are therefore used by these people (mainly Jaws

and NVDA). In terms of IT skills, marked differences

therefore exist between the partially sighted and the

blind.

Because of the general demand for IT-skilled per-

sonnel (Pauly and Holdampf-Wendel, 2019), a num-

ber of gateways to typical IT problems have been

developed. One such attempt is the development

of education-oriented programming languages, which

are intended to support the ﬁrst steps in program-

ming (Grover, 2015), speciﬁcally for children (Baron,

2014). While these web-based programming environ-

ments have been widely successful, their accessibility

The “network for the professional participation of blind

and partially sighted people” has put together 58 qualiﬁca-

tions for the administration activities, telecommunication,

commercial occupations, the skilled trades, landscaping,

healthcare and artistic occupations. There is also training

at universities.

for the blind and visually impaired is questionable. In

the following, education-oriented programming lan-

guages are introduced (while distinguishing graphical

and tangible programming), then, guidelines for the

veriﬁcation of accessibility are presented, which are

then used to evaluate 17 programming environments.

2 EDUCATION-ORIENTED

PROGRAMMING LANGUAGES

Many of the common programming learning envi-

ronments are based on simpliﬁed programming lan-

guages, where the syntax is reduced to the essentials.

With semantic, syntax and type errors being typical

mistakes among novice programmers (Altadmri and

Brown, 2015), this allows beginners to focus on se-

mantic properties but also decimates the possibilities.

The text-based, graphical or tangible programming

languages and environments presented in this chapter

were found through:

• literature reviews of novice programming en-

vironments, mostly comparing text-based and

block-based programming environments, such as

(Xu et al., 2019),

• a web-based search, where websites (such as

(Baron, 2014)) were used to ﬁnd easily accessi-

ble programming environments for children.

Although introductory courses exist for most of the

commonly used programming languages (such as

Java and Python), several text-based programming

languages and environments were speciﬁcally de-

signed for novices. One famous example is BASIC,

which stands for “Beginner’s All-purpose Symbolic

Instruction Code” and was developed in the 1960s

(Kemeny and Kurtz, 1971). BASIC has since been

widely used as an introductory programming lan-

guage due to its simple syntax (Kemeny and Kurtz,

1971). Many so-called “dialects” of the programming

language were developed, including Visual Basic and

VB.NET, which belong to the most commonly used

programming languages (Stack Overﬂow, 2019).

Other examples of novice programming languages

include Lisp and Logo, which is a variant of Lisp.

These languages were developed at MIT in the 1950s

(Papert, 1978; Winston and Horn, 1986). Whereas

Lisp was mainly developed for the processing of lists,

Logo was developed especially for the introduction

into programming paradigms for children. Variants

of both programming languages are still used today.

Furthermore, programming environments target-

ing children as novice programmers were developed.

Evaluation of Low-threshold Programming Learning Environments for the Blind and Partially Sighted

367

KidsRuby (The Hybrid Group, 2011), for exam-

ple, is a programming environment for children and

teenagers that uses a simpliﬁed version of the Ruby

programming language. An exemplary code is dis-

played in Listing 1.

Listing 1: An example of KidsRuby code.

T u r t l e . draw do

b a c k gr o u nd b l a c k

p e n c o l o r r e d

1 0 0 . t i m e s do

d i s t a n c e = r a n d ( 1 0 0 )

t u r n r i g h t r a n d ( 2 5 )

f o r w a r d d i s t a n c e

bac kwa r d d i s t a n c e

end

The commands that can be implemented in KidsRuby

can be used without instructions, the syntax includes

for and while loops, but without the need to imple-

ment variables.

In the next subsections, we will introduce graphi-

cal and tangible programming languages and environ-

ments, to assess their extent of accessibility for the

blind visually impaired in the following sections.

2.1 Graphical Programming Languages

Building on top of the text-based programming lan-

guages (such as Logo), new languages and pro-

gramming environments have been developed specif-

ically in order to further ease the access to program-

ming. More so than text-based programming envi-

ronments, graphical programming environments have

been found to appeal different students in primary

and secondary education (Papadakis et al., 2019).

The so-called graphical programming languages rep-

resent an attempt to reduce the susceptibility to er-

rors in the syntax of programming languages by us-

ing ready-to-use building blocks. It is inconclusive,

however, whether they should be preferred in com-

parison to text-based programming languages (Price

and Barnes, 2015; Xu et al., 2019)

As one of the most prominent representatives of

graphical programming languages, Scratch was de-

veloped and published in May 2007 by a team from

the MIT Media Lab (Resnick et al., 2009). Scratch

is a visual, lisp-based programming environment for

children and teenagers that has approximately 40,000

users per day (Scratch, 2013).

As can be seen in Figure 1, the syntax contains blocks

(so-called scratch blocks) that are joined together by

Figure 1: Sample implementation in the scratch environ-

ment.

drag & drop. The different colors and shapes sym-

bolize different command groups (e.g. movements in

animation or sounds) and their modality (e.g. loop,

deﬁnition, if query). Scratch is cloud-based and runs

without installation in the browser. Spin-offs running

as apps (such as Hopscotch for iPhones and iPads

(Hopscotch Technologies, 2019)) were developed as

alternatives. Other graphical programming environ-

ments that were inspired by Scratch, or represent ex-

tensions, include:

• Snap! (BYOB): Snap! (Moenig and Harvey,

2009), which used to be called “Build Your Own

Blocks” was developed by Jens M

onig and Brian

Harvey (Harvey, 2019) at the University of Cali-

fornia, Berkeley, in 2009 (Scratch, 2013). Snap!

is an extension of Scratch in the way that it offers

more complex functions and concepts for imple-

mentation.

• OpenRoberta: OpenRoberta (IAIS, 2014) is an

open source programming environment at the cen-

ter of the Roberta Initiative of Fraunhofer IAIS,

Sankt Augustin (IAIS, 2014). The programming

language NEPO used in OpenRoberta, which was

designed based on Scratch, is developed as Open

Source and is suitable for use with robots such as

EV3, Calliope, Arduino, etc..

• MIT App Inventor: Originally developed by

Google and later adopted by MIT, MIT App In-

ventor is a graphical programming environment

for developing apps (MIT Media Lab, 2010). The

environment consists of two layers (design and

block editor) representing the front and back end

of app development. Both levels were developed

in the style of Scratch and use a syntax of building

blocks that are inserted by drag & drop.

Other programming environments worth mentioning

are Alice, a block-based programming environment

CSEDU 2020 - 12th International Conference on Computer Supported Education

368

for creating 3D animations (Alice, 1995) and Kodu

(Microsoft Research, 1999), which is also imple-

mented in a 3D environment using building blocks.

Their goal is primarily the development of games.

Even though the graphical programming environ-

ments bear similarites, they mostly target different

age groups, or programmable features (Kaya and

Yıldız, 2019). As for their ﬁtness for the blind and vi-

sually impaired, this will be systematically evaluated

using criteria deﬁned in Section 4.

2.2 Tangible Programming Languages

Tangible programming, meaning programming based

on haptic objects, began at the MIT AI Lab. Using

the programming language Logo, Papert and his col-

leagues developed a hemispherical robot (”TORTIS”)

that could be controlled with simple commands such

as forward, backward, left, right (Perlman, 1974).

Based on these results, Perlman developed new user

interfaces and designed prototypes in box form, with

haptic buttons and levers

One branch of tangible programming consists of

programming robots. Several robots can be pro-

grammed by simulating certain sequences. Topobo

(MIT Media Lab, 2003) for example is a robot with

two states (active/passive) in which motion sequences

can be stored and executed. The shape of the robot

is shown in Figure 2. Another example is Curlybot

(MIT Media Lab, 1999), a hemispherical robot devel-

oped by MIT Media Lab, which stores and reproduces

movements.

Other variants of haptic programming languages

include

• Primo (Cubetto, 2017): Cube-shaped wooden

robot that can be programmed on a control board

using pluggable coding blocks.

• Tangible Programming Bricks (McNerney, 1999):

Haptic blocks with different functions that are

1) plugged together to implement or 2) equipped

with parameter cards (see Figure 3 for an illustra-

tion of the haptic programming blocks).

• Tern (HCI Tufts, 2008): Different blocks of wood

are plugged together for programming. The con-

ceptual structure of the programming language is

very similar to that of Scratch and it can be used

to create programs for robots of the LEGO Mind-

storms RCX series.

• Strawbies (Hu et al., 2015): Haptic puzzle pieces

are put together to create a virtual simulation.

• Cubelets (Cubetto, 2017): Modular robot de-

signed by selecting its components.

Figure 2: Topobo, a robot that can be programmed by ex-

amples. The image was taken from the ofﬁcial homepage

(MIT Media Lab, 2003).

• Note Code (Kumar et al., 2015): Puzzle tool

with musical function, to teach programming

paradigms.

Figure 3: Tangible Programming Blocks. Figure by McN-

erney (McNerney, 2004).

3 WEB CONTENT

ACCESSIBILITY

The World Wide Web Consortium (W3C)

is an in-

ternational community that develops standards for the

accessibility of web content. In order to be accessible,

web content must be:

www.w3.org

Evaluation of Low-threshold Programming Learning Environments for the Blind and Partially Sighted

369

• Perceivable: text alternatives available, descrip-

tion of elements available, sufﬁcient color con-

trasts

• Operable: usable without mouse, content can be

viewed for a sufﬁciently long amount of time, no

content, which might cause seizures or physical

reactions

• Understandable: structured, e.g. with titles, easy

language

• Robust: compatible with commonly used assis-

tive technology

To test webpages for the conformity with the acces-

sibility standard, several tests have been developed

(BIK, 2019; ACT task force, 2019). Depending on

the testing procedure and the web content, conformity

levels from A to AAA with the Web Content Accessi-

bility Guidelines can be earned (Consortium, 2019).

In order to make web content accessible, several

aiding tools exist. Perhaps the most commonly known

tool for aiding people with blindness and visual im-

pairments are Braille fonts or displays. This font dis-

plays letters as tactile representations, using raised

dots in rectangular block-formation. Other formats

are Braille writers, notetakers or embossers, where

notes can be taken in the Braille font.

However, when it comes to the best ﬁtting tools,

people distinguish between blindness and visual im-

pairment. A group of software aimed at aiding the

visually impaired are magniﬁcation softwares, which

magnify content on the screen. Examples are prod-

ucts made by Google

, MAGic

or SuperNova

. Fur-

thermore, video magniﬁers are electronic visual aids,

which record writings using a camera and display

them strongly enlarged on the screen.

For the blind, several software products are com-

monly used as aids in order to make computer- and

web-content accessible. Among them are screenread-

ers, which read the content on the screen and either

read it out loud or display it on a Braille display. Ex-

amples of such software include JAWS

, the openly

available NVDA

and SuperNova

https://www.google.com/accessibility/. Last accessed

30.10.2019

https://www.freedomscientiﬁc.com/products/software/

magic/. Last accessed 30.10.2019

http://www.dolphin-de.de/produkte/dolphin/supernova-

magniﬁer-screenreader/index.html. Last accessed

30.10.2019

https://www.freedomscientiﬁc.com/products/software/

jaws/. Last accessed 30.10.2019

http://meinnvda.de/. Last accessed 30.10.2019

http://www.dolphin-de.de/produkte/dolphin/supernova-

magniﬁer-screenreader/index.html. Last accessed

30.10.2019

In the IT sector, the blind and partially sighted

are generally trained using common text-oriented pro-

gramming languages such as Java, Sharp and SQL.

The web languages PAP and Framework are also

learned. These languages are very accessible be-

cause they consist of understandable texts. The lin-

ear progression of the language is like the output of

the screen reader. By contrast, for example, C poses

a particular challenge for the blind because the com-

mands produce no readable words due to the symbols.

This means the symbols cannot be read out by the

screen reader and therefore mastery of the Braille dis-

play is required.

4 SYSTEMATIC EVALUATION

To evaluate programming environments for beginners

and children, we have distinguished 6 categories, in

which the programming languages will be examined,

in order to ﬁnd their measure of accessibility.

Alt-text. Using the Google Chrome extension “Alt

Text Tester”, it was checked whether all of the im-

ages had alternative text descriptions.

Font Size. It was checked to see whether the font size

can be enlarged without endangering the structure

and make-up of the website.

Keyboard Usable. It was checked to see whether

the website is navigable using only the keyboard

via prompts deﬁned in (Accessibility Developer

Guide, 2018).

Contrast. Contrast of at least 1:3 for important items

(text, graphics) was checked via the Color Con-

trast Analyzer extension for Google Chrome in

accordance to the BITV testing procedure (BIK,

2019).

Content. It was determined, whether the language of

a website could be automatically detected using a

web service

. This may be necessary for reading

software.

Robustness. To ensure that all viewers of a web-

site can display and process it correctly, it is

very important to specify the character encoding

(’charset’) correctly. False encoding can cause

problems for assistive technology. The robustness

was checked using the W3C validation service

as recommended by (Faulkner, 2019) and returns

the errors in the character encoding.

https://translate.google.com

https://validator.w3.org/

CSEDU 2020 - 12th International Conference on Computer Supported Education

370

Table 1: Testing procedures for the accessibility of programming environments for children and beginners. Some of these

environments were only accessible through an application that could not be tested for robustness. In these cases, the robustness

is unknown.

Language Alt-text Font size Keyboard

usable

Contrast Content Robustness

KidsRuby 7 3 7 3 3 application

Scratch 7 3 7 7 3 1 error

Hopscotch 7 3 7 7 3 application

Snap! 3(no images) 7 7 3 3 5 errors

OpenRoberta 7 3 7 7 3 285 errors

MIT App In-

ventor

7 3 7 7 3 6 errors

Blockly 7 3 7 7 3 (not found)

Alice 7 7 7 3 3 application

Kodu 7 7 7 7 3 application

Swift Play-

grounds

7 7 7 3 3 application

Kodable 3 3 7 7 3 9 errors

Thimble

moz://a

3(no images) 3 7 7 3 7 errors

Code Monster 7 3 7 7 3 22 errors

Gameblox 7 3 7 3 3 10 errors

Code.org 7 3 7 7 3 54 errors

Tynker 7 3 7 7 3 48 errors

These categories were chosen as a minimal represen-

tation of the 60 test items of the BIK (BIK, 2019),

which is a test procedure for the comprehensive test-

ing of the accessibility of websites. These criteria are

all required for the lowest level of accessibility (A)

and may easily be replicated on any typical computer

using open online resources. Since these conditions

were directly picked from the BIK items, any web

content, which fails to fulﬁll these conditions, will

deﬁnitely not be classiﬁed as accessible by the larger

catalog of requirements.

5 RESULTS AND DISCUSSION

The advancing digitalisation can represent an oppor-

tunity but also challenge for the blind and for the par-

tially sighted. A key criterion in this regard is acces-

sibility. If the trend towards accessibility is contin-

ued in the context of the digitisation process, this may

result in very good future opportunities in terms of

labour market integration for the blind and partially

sighted as a group. However if the opposite trend con-

tinues, the blind and partially sighted will ultimately

be largely excluded from digital work processes.

The IT sector has for some years already been of-

fering a range of employment opportunities for the

partially sighted and for the blind. Besides the activ-

ity of programming, working with databases is also

possible for those concerned. Working in the area of

testing is generally also possible provided the testing

tools used are accessible. Some areas such as soft-

ware planning continue to represent a risk of exclu-

sion due to the two-dimensional graphical language

standards which is virtually impossible to represent

in text.

Within the scope of this evaluation, 17 computer-

based and 6 other programming languages were pre-

sented and evaluated. Most of these were evaluated

using the criteria deﬁned in Section 4, which were in-

troduced as a minimal check for accessibility of web

content. The results are visible in Table 1.

Most of the programming IDEs were implemented

in a responsive format, allowing the font size to vary

ﬂexibly. The content was suited for children, with

easy and clear language that could be identiﬁed pro-

grammably. The programming environments that

were tested were not completely navigable by the

keyboard and thus not deemed operable. This in-

cludes the web-based, as well as the locally operat-

ing software. In particular, the widely used graphical

programming environments based on drag-and-drop

blocks used in Scratch and Scratch-like IDEs are not

suitable for the blind and visually impaired. Apart

from missing alt-text descriptions, the sites were not

operable using only the keyboard. Therefore, our

current ﬁndings indicate that the widely used (web-

Evaluation of Low-threshold Programming Learning Environments for the Blind and Partially Sighted

371

based) novice programming environments are cur-

rently not suited to be used by the blind and visually

impaired.

Other alternatives, such as robots, can reproduce

movement, and may be used by people with visual im-

pairments, but they offer little leeway in programming

their own functions. Classic programming paradigms,

such as for and while loops, cannot be learned from

these robots. The other haptic programming lan-

guages (e.g. Tern and Tangible Programming Bricks)

could, in general, be used by blind and visually im-

paired people. In their currect form, however, the

blocks would have to be supplemented with Braille

lettering or other haptic features to identify the indi-

vidual functions.

In principle, the current investigation has also

shown that classical programming languages (such

as PAP and Framework) may be more accessible as

starting points for beginners, since the syntax con-

sists of understandable texts and may be used in com-

bination with tools, such as a screen reader. How-

ever, low-threshold programming environments for

novices, who are blind or visually impaired, are

scarce.

6 CONCLUSION

In total, none of the 17 graphical programming en-

vironments were suitable for the usage by blind and

visually impaired people. Some text-based program-

ming languages were deemed more accessible as a

starting point for programming. However, in re-

cent decades many approaches to haptic program-

ming have been published which may be extended

for use by blind people in the coming years. Due to

the great success of low-threshold graphical program-

ming languages with sighted people, corresponding

offers should also be developed for blind and visu-

ally impaired people. This might pave the way for IT

skills to be developed later in life.

ACKNOWLEDGEMENTS

We thank Ottfried Altfeld, Head of the Department

for Participation and Vocational Education and Train-

ing at blista, the German Institute for the Blind,

for their friendly support. This contribution was

funded within the framework of the BMBF joint

projects “Learning Analytics und Diskriminierung”

and “DABEI: Digitalisierung in der betrieblichen

Ausbildung von Menschen mit Behinderung”.

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