Line a baking sheet with parchment paper or wax paper.
Roughly chop chocolate and add it to a double boiler (or in a heat-proof bowl set over a saucepan with water) and bring water in the bottom of boiler to a boil. Stir the chocolate with a wooden spoon until it's evenly melted and smooth (see post body for more options on how to melt chocolate).
Dip graham cracker squares one at a time in melted chocolate. I recommend using two forks to dunk them and flip them to ensure the grahams are fully coated. Lift the graham cracker with a fork and gently shake off excess chocolate and use fork to smooth if desired. Place the chocolate graham on the prepared baking sheet.
Add sprinkles to graham crackers while chocolate is still wet.
Let chocolate graham crackers set and harden. You can leave them at room temperature for an hour or so (depending on the temperature of your room) or speed up the process by letting them chill in the fridge for about 30 minutes.
To store, keep graham crackers in an airtight container, separated with layers of wax paper to prevent sticking. When stored properly, they should keep at room temperature for about 2 weeks or in fridge for about 3 weeks.