You can definitely add the link to your webmix on your website or blog. Share your webmix and grab the URL (e.g. http://www.symbaloo.com/mix/tuesdaytutorial) from the Webmix Details.
But we actually have something even better. You can embed your webmix directly on to your site so that the students could just access the resources directly from your class site. You can create separate pages on your site for each grade and embed the webmix for each on the different pages.