Online Writing Labs, or OWLs, have been a prominent web-based source of help for college writers since the mid-1990s. The oldest (and perhaps still the best) OWL, at Purdue University, has expanded its audience to include educators for grades 7-12 and parents. Check out their resources and see if the Purdue OWL might be something you'd like to share with students and/or parents, or use its resources in your own teaching.
If you're feeling tech-savvy, you might want to create an OWL of your own. Here's one from the Edina school district for elementary students. It's Six Traits-focused only, but shows what a minimal OWL might look like. OWLs began mainly as a repository for handouts, but with the expansion of technology, you could put videos on an OWL, create a discussion space for writers, have a way for writers to post their writing for feedback, have self-quizzes or online tools for writers--all kinds of things.