In all three versions of Super Mario Bros 3, there is a glitch in level 1-5. Have fire power, go to the last cave, where the Venus Fire Trap and the upside down piranha plant. Go to the slope, and face left. Jump up and shoot your fireballs, you should see the fireballs go up through the ceiling, and I know it can be done in all three games, SMB3, SMAS and SMA4. But it's easiest to see in the NES version since it's all white. Not a major glitch I know. I found this a LONG, LONG time ago, when the NES was new. and I noticed it was not on the website. So I decided to share my knowledge.