They are of the globe variety, with a hot and quite fiery taste - a little bit too peppery for my son. For me they brought back memories of my childhood with my family growing them and cutting crosses in the top to open them up into star shapes. We also used to have great fun making vegetable faces with them and other vegetables.
They are ideal for taking on picnics. Although they look good with leaves on we took them off of ours before storing to prevent goodness travelling up to the leaves.
We will definitely be sowing so more this summer though will take the advice from Love radish to sow a purple variety with a milder flavour perhaps more suited to younger children.
We have a sister site kidsinthegarden which has a wealth of information on growing vegetables with children.