At the beginning of the season they produce mainly female flowers. The male ones should appear before too long. In the meantime you could try making fritters with the female unfertilised ones (never tried it but seen it recommended)

its the female flowers you need to form the courgettes. so perhaps so far you have just had male flowers. often too dry an atmosphere is the cause. try misting the plants to increase the humidity. are they outdoors or indoors? my daughter grew some in the greenhouse and she had to wet the floor every morning before going to school to get any fruit. she didn't bother growing them after an extra early start :o)

I meant that the female ones wouldn't set without the male ones...perhaps i got iot the wrong way round and its the male ones that usually appear first, but the results are the same...