To crush graham crackers, add them in a small zip-top bag and close it tightly. Smash the graham crackers in a small rolling pin or bottom of a measuring cup until no large pieces remain. Set aside.
Using a microplane or other zester, remove the bright green zest from the lime. Add to your blender. Roll lime on the counter, pressing firming, to release the juices inside. Cut lime in half then juice it into a small bowl. Measure 3 tablespoons of juice into the blender.
Cut avocado in half then use a spoon to remove the pit. Scoop the avocado flesh into the blender. Make sure to scrape the inside skin to get every bit off.
Add maple syrup, milk, vanilla, and pinch of salt (in brings out the flavors) to the blender then blend until completely smooth. Taste then add more sweetener, if desired.
Pour the avocado mixture into popsicle molds, sprinkling layers of graham cracker crumbs in between if you'd like. Tap your pop molds on the counter while filling to release some of the air bubbles. Once popsicle molds are full, sprinkle some graham cracker crumbs on the top, if desired.
Freeze until solid, at least 8 hours or overnight. To remove popsicles from the mold, run under very hot water for a few seconds. Store popsicles in the freezer, well covered, for up to 2 months.