Of course it's not toxic* and it's not particularly slimey, but I find anything a bit nasty, creepy or dangerous is entirely appealing to little boys.
I've had homemade playdough on my to-do list for a while now, and this weekend we had the perfect rainy day to whip some up. I love anything I can make in a matter of minutes (i.e. my only window of opportunity, Vin's naptime) and from kitchen ingredients too!
1 cup plain flour
1/2 cup salt
2 tbsp cream of tartar
2 tbsp vegetable oil
1 cup water with food colouring added
and because I am probably a little weird, I added some peppermint flavouring to make my dough smell nice, though you could use vanilla extract or almond essence
* mix all the ingredients in a large pan - stir over a medium heat for a couple of minutes - the mixture will turn lumpy first, like chocolate when it seizes, keep stirring and within a couple of seconds you will have a lovely gooey dough
* knead for a couple of minutes until soft and stretchy (I can't tell you how weirdly pleasurable this bit was)
* store in an airtight container or ziploc bag
You could make up little pots and team with a set of palstic cookie cutters as a little treat - I see toddler party favours in the near future
This makes a lot of dough, so I would suggest splitting it into a couple of pans and making a couple of different colours. If you're not into the green and slimey, maybe pink colouring with a drop of rose water (I think I would have to chuck in some lustre dust or glitter too!)
* p.s. this mixture is non-toxic, but it tastes very salty
p.p.s. so far the green colouring hasn't stained our white tabletop, clothes or hands