Application for learning English with automatic listening, speaking, grammar and vocabulary training options

To create a distance learning system that allows to practice all the necessary skills for learning English.

Nowadays, more and more educational institutions provide their services online. This trend existed before the COVID-19, but since the pandemic began, it has increased significantly. Since distance learning is much more scalable than traditional one, the capacity of a virtual classroom can be 20, or 100, or 1,000 students. At the same time, the more a person is involved in the learning process, the higher the cost.

We were approached by an English teaching company. They wanted to create a distance learning system that allows to practice all the necessary skills for learning English so that most of the tests could be conducted automatically.

The development of an application enabling teachers to conduct lectures with sharing desktop function and students to practice listening, speaking and grammar skills individually.

The majority of companies that provide distance learning services implement their educational platforms, based on already existing products from third parties. For example, they use Skype or Zoom for audio and video conferencing with teachers, Google Forms to create a student's knowledge review tests, YouTube to post some videos, and so on. This approach is quite acceptable, but it has a significant flaw: all the products used to create the platform belong to different companies, and all of them have different user agreements, all of them are existing and developing independently.  All changes to the terms of use and functionality of these products must be constantly monitored, all adjustments should be made in time, otherwise some parts of the platform may suddenly fail.

Private platform, entirely created in a training company, is free from such imperfections, but its development causes much more expense. The development of a custom platform based on Amazon services, primarily the Chime service, is a reasonable compromise between the flexibility of your own solution and the cost of creating it from scratch. And besides the Chime, AWS has a wide variety of tools for this purpose.

Our application provides users with the following features:

• The teacher conducts lectures in a video conference format, sharing a desktop to highlight the important issues of the presentation to students.
• The teacher explains the mistakes in students` tests, also in a format of a video conference with desktop sharing.
• The student individually trains the listening skills, watching videos and listening to audio recordings, and writes down what was heard in a text format. The platform evaluates the correctness of that text.
• The student individually trains grammar and vocabulary knowledge, fulfilling pre-planned tasks in the platform.There are several types of exercises: filling-in missing words and constructions into the text, correcting errors in the text, choosing the missing grammar construction from a number of options.The platform compares the results of the exercises with the prepared answers.
• The student individually trains the pronunciation skills, reproducing the text in a voice according to the example.
• The student pays for classes using one of the payment system options connected to the platform.

Mobile and web application for students and teachers based on Chime Platform; implementation of Elemental MediaConnect for broadcasting audio and video, S3 and RDC for storing data and Cloudfront as a CDN.

Our platform supports two types of client applications for students: mobile and web application. In addition, it supports a web application for teachers, which allows to conduct lessons using the platform's materials.There is also a platform admin interface that enables inserting training materials as well as monitoring the payment balance of each student. The server side of the system includes using of the following Amazon services:

• Chime is used for audio and video conferencing and desktop sharing;
• Kinesis Video Streams for broadcasting audio and video files uploaded to the platform;
• Amazon S3 - for storing audio and video files;
• CloudFront as a CDN (Content Delivery Network);
• MySQL for storing students` test and training results;
• Amazon Lex to check pronunciation.