For me, I equate sensory bins with all 5 senses not just touch or texture (i.e. sand, water, rice, goop, cornmeal). I've put in an assortment of shakers for my toddlers for their hearing sense, large feathers for their touch sense, we've done the cheerio bin (toddlers love this one, play and eat at the same time) for their taste sense etc... However, when I say I add blocks to the sensory bin, I mean that I add all blocks that are round only or only yellow blocks if yellow is the colour we are focussing on that month. All my bins are always theme related, right now we are beginning to talk about apples and I have a bunch of fake apples in there. Next to it is a bucket with a branch and the children like to hang the apples on the branch.