What are some alternatives?
When comparing edx-platform and Open edX, you can also consider the following products
Chamilo - Chamilo is a software that allows you to create a virtual campus for the provision of online or semi-online training.
Moodle - Moodle - Open-source learning platform | Moodle.org
Edmodo LMS - Edmodo is an easy way to get your students connected so they can safely collaborate, get and stay organized, and access assignments, grades, and school messages.
Khan Academy - Khan Academy offers online tools to help students learn about a variety of important school subjects. Tools include videos, practice exercises, and materials for instructors. Read more about Khan Academy.
Google Classroom - Learning management tool by Google
Coursera - Build skills with courses, certificates, and degrees online from world-class universities and companies