Clare - when DH is away on a weekend I hatee it - i dont want to land myself on my friends who are probably having family time and as you know my family isnt here...
I try to make it really fun for N - so that he doesnt whinge and also to tire him out for a long midday nap and a good sleep at night. and i treat us both...
so some ideas:
Scienceworks
Aquarium
(mum took N to these both last week and both were a hit)
Good play at the park at the MCG followed by lunch at Victoria st
Collingwood farm
Birrarung Mar and lunch in the city

I also do milkshake trips or out for a bubacino and cupcake
do some cooking togther at home
paintings for daddy

i also love taking N on the trams or train in Melb to some of these outings... i also saw there is a boat from the city to scienceworks - could be cool???