I dyed a mass of rice the other week for the class I assist at school to do some Rangoli with. Since I was already spending the evening on a rice-dying frenzy* I thought I'd add an extra batch in for Kit (I actually held back a bit of each colour for him so we can do some more things later on).
For our first foray into dyed rice, and for a more age appropriate dyed rice activity for a three year old, we used it for a bit of sensory play. Kit does a lot of pouring and spooning and tweezering of stuff at pre-school, as part of their Montessori activities, which I'm guessing influenced his choice of what he wanted to do with the rice. I presented him with the rice in a litter tray (classy!). We then collected a range of utensils and containers from the kitchen and I left him to his own devices. He said he was making cakes and we added in some coloured pencils for him to use as candles. Mainly he was just pouring and spooning it from one container to the other, and he enjoyed sitting playing with the rice for ages (which is a miracle for a child who suffers from ant-in-pant-itis). We'll be playing with it a lot more before we might actually use it for an art and craft based activity, I'm interested to see where his imagination takes him the next time I get it out.
*I dyed the rice by mixing the cheapest rice that I could find with some food colouring until it looked the colour I wanted, spread it out on a baking tray and left it overnight.