Oregon Zoo is only $4 on the second Tuesday of each month.
Oregon Historical Society Museum is free for Multnomah county residents.
OMSI is only $2 per person on the first Monday of the month.
Portland Children's Museum is free each first Friday of the month after 4 PM
Portland Art Museum is free each 4th Friday of the month from 5-8 PM
World Forestry Center offers $3 admission on the 1st Wednesday of each month.
