Vegetables are REALLY interesting...no, really! Babies will eat anything that is fed to them, and aren't discerning about vegetables. Most toddlers will eat most vegetables too and not question them, but as they grow older, and perhaps helped by peer pressure as their social networks grow, children might decide that they don't like certain, or even any, vegetables.
Is it the colour? ...the texture? ...the taste? There are a multitude of reasons why children may begin to turn their noses up at vegetables, but do what you can to fight their reluctance and try to keep vegetables firmly on the agenda.
One way to make vegetables interesting is to have children think about them properly. Make a vegetable chart and depending on how old your children are, order them in different ways.
The youngest children will be able to order by size or to sort them by colour. Older children might be able to start with the sweetest through to the most bitter. You may even be able to teach them about seasonality. Although most vegetables are now available from the supermarkets all year round, there is a pattern of seasonality at which point differet vegetables are available. Perhaps you don't know yourself? In which case, spend time with your older children looking at the seasons of vegetables. Work out which are traditionally available in spring, summer, autumn and winter!