My first week in Panama City I noticed that there are large number of School buses that are decorated with psychedelic or religious symbols , bright led lights, and long vertical exhaust pipes  creating more noise to the already congested  streets. Often these buses are very crowded, the locals tell me that they are only 25 cents to get on. American currency is accepted as long as it is not over 10 dollars. You will notice that they have specific destination written on the front of the bus, and quickly learn that they only have one destination and will not alternate their path.  At first I believed you can find a schedule online but quickly realized that it is non-existent. The best way to approach this ordeal is to download map:  www.panama-maps.com.  This is the least expensive transportation that is very accessible, and definitely is the most memorable for those that really want to experience the rich culture of Panama city.