M.R.
Ringworm is contagious. It continues to be contagious until the 'ring' goes away. Before you send your child to daycare with ringworm, think of it this way: what if another child with ringworm went to daycare and spread it to your child and then you had to take him to the doctor, pay money, and then take time off of work because he's contagious? I'm going to guess you'd be annoyed at the least and possibly angry.
Call the daycare and ask them what their policy is on ringworm and follow their advice.