Painting the fence with water works well on a hot day.By the time they get to the other end,the first bit needs a recoat.
The sand table's a big hit in our garden this year,even with the older children.My 9 year old is currently making sand birthday cakes with my 2 and 3 year old.
I give the kids ordinary wipes for cleaning.We don't clean our car,it's a minibus so I park it on my parents drive,that being a convenient slope, and jet wash it out the back doors but seat dirt will come off quite well with your basic baby wipes.
Making camps is another big hit.Our shed is full of safe" stuff".Curtains,a windbreak,things they used to ride on,just stuff.Indoors we have plenty the same.We have a toy chest full of hats,bags,wigs,blankets as well as the proper costumes.The imagination is a wonderful thing.
The wii,ps3 and xbox are always on somewhere,just seems a shame to be inside wasting such lovely weather that kindly arrived for the holidays.