My 6 year old has a fever of 103. Gave her some ibuprofen about 20 min ago and now her temperature is 102. What else can I do to get her fever down?

Call pediatrician. It is common to alternate Ibuprofen with tylenol (acetaminophen) when one is trying to bring down fever every few hours. In addition please sponge the child's body soaked in tepid water as when water dries off the it cools it down. Call the pediatrician for advise as the source of fever usually an infection needs investigated immediately.
See below. A cool bath may help. If the fever persists or gets higher you need to see a doctor.
Fever. Fever is a reaction of body to infection/inflammation. Fever reducers takes time to bring the temperature down and if fever high grade may not come to normal body tempertaure. Luke warm bath or cool wash cloth can be used for high fever 103/104 f along with fever reducers for high fevers one can alternate tylenol/motrin every 4 hours. Motrin recommended for a 6 month old infant.