I wouldn't do anything with themes for schoolchildren (unless it's Pancake Day or whatever). I think there are a few old threads about entertaining older children.
All the usual stuff really - any art/craft stuff, playdough, Lego/construction sets, board games, games console/TV (limited), stuff they can help themselves to if you are busy with littlies. In nicer weather - lots of outdoor play and walks to park.
I do monthly newsletters, given to each family I mind for. I nearly always have a child with a birthday each month, so put in a photo and "happy birthday" type message. (If they have turned 5 or 8 years, it generally includes a "yippee" for clearing a space within my numbers!)
I include photos/information of what we have during the month. If I've done any courses/workshops, I write a short blurb on that (not to sing my praises, because I am usually too sarcastic, particularly if it's yet another Ofsted requirement).
Having just typed all that, I realise that perhaps you mean written info for parents about what their child has done?? If so, then I don't do that because children are more than capable of talking about their day. But they would get one of my ultra-professional newsletters each month.