To begin with, these are the links to two really useful resources. The first one is a PDF file containing the book English Grammar Secrets. It includes explanations of basic grammar points and online activities. This link will direct you to the activities online. If you want the PDF, bring a USB to class, or send me your email address.
English Grammar Secrets
The second is a blog called El blog para aprender inglés. It offers hundreds of possibilities such as courses, videos, explanantions... Have a look and explore it!
El blog para aprender inglés