OWL ontologies on the cloud

My goal is to make a web application that imports an owl ontology that we created in e.g. protege that represents a learning domain e.g. "Math".

The admin of the web app will then create lessons/learning targets using a subset of that ontology (for example "multiplication of 2 integer numbers").

What tools will allow me to create a sub-ontology of the imported one and perhaps edit it, create individuals etc. on the web? I will need this sub-ontology to be downloadable. Is there a java jena alternative for the web? perhaps a php library?

Thanks in advance