Little practical application exists for making change for a dollar using 50 coins. It is a fun math problem, though. Ask Dr. Math notes two possibilities -- one with 40 pennies and another with 45 pennies. The simplest approach is with 45 pennies.
Count 45 pennies
Count out 45 pennies, and set those aside. This step leaves five coins for the remaining $0.55.
Add a quarter
Add one quarter to the pennies to reach $0.70. A quarter is necessary because five dimes is only $0.50.
Add dimes and nickels
Dimes and nickels cover the remaining four coins for $0.30. Since three dimes is $0.30, only two dimes are possible. Thus, two dimes and two nickels complete the 50 coins for $1.