I took part in development of system for online education for elementary school. Project includes online tests with simple logical tasks and reaction/attention test. There are also simple logical/arcade games.
Project built with PHP, Yii1 and Mysql as a database. Hosted on Amazon EC2 and RDS. S3/Cloudfront is used as external file storage. Stripe is used for payment processing.
I took part in project while I was working in Yumasoft inc.