Dog barking at us to play!

Hi,
I have an 8 month maltese/poodle mix. He is a great dog, super friendly and affectionate and well behaved for the most part. Lately he has started barking at us to play with him(sometimes bringing over a toy to us) while we are on the computer, reading, etc(but not paying attention to him). Usually we will throw it a bunch of times, but then need a break. He gets lots of attention and tons of excercise.

I am not sure how to handle this...I have been verbally reprimanding him with a firm "NO". He looks a tad phased, but then continues. When he first started this we thougt it was funny and kept throwing his toy for him, but now it is getting annoying and I think he is getting a little too full of himself. I have been told when he was very young that we should be the ones to initiate play, not him. At the time it wasn't an issue, so we let our guard down.

Sometimes, especially with my 9 year old daughter and husband he will jump up and nip at their pants to try to get them to play and chase after them. Naughty :)

Any words of wisdom?

Chris(and Charlie)