If processing input is also part of working memory then encouraging retelling of stories could help. They Always want to tell you what you just saw on tv even though you just saw it. I should probably quit now because I don't what you're trying to work exactly. I think that's how they're enlarging their working memory, by talking outloud.
OMG! I'm so glad to hear you say this. ha! My husband and I are always wondering if other kids do this. It drives us crazy, but we try to just listen. Then we laugh about it later. We're thinking, "yeah, I know, just watched it with you!"
