Maybe mix it with something they like (maybe something unhealthy), but dont sit them side by side on the plate( Incorporate them in a mixture).
You could even start with stir-Fry Veg !! Use some nice tasty sauces when serving them up. Like a Tomato/Napolitana type sauce (Dont forget to add sugar to counteract the acidity of the Tomato and the kids will love it). Use fresh herbs.
Or you could try Rattatouille. Look at some vegetarian recipes but serve them up as your side veg. its a quicker way of getting your kids to eat the veg. if youre going to serve up the veg as it is, then dont forget to put salt in the water before you boil your veg. Hope it helps. :-) Good luck.