Have you looked in our
'Recipes' forum? There are some ideas for play dough types materials that are made from natural ingredients - you wouldn't have to worry about any tasters then!
Also check out
'The Senses' forum for some great ideas.
Build A Tent In Your Garden and adapt it for indoors.
Noisemakers 
My DD loved getting a big bowl of dried peas or beans and plastic spoons and cups, wooden utensils etc and just stirring and generally making a mess - but because they're dried and fairly large the beans/peas are very easy to find when it's tidy up time. :jump:
Hope this helps.
Tracey.