I loved the twist at the end where the mysterious monolith ended up being nothing more than a glorified appliance. It was an amusing twist after some excellent buildup in Dilby's (and the audience's) expectations. You also did a great job with Dilby's character, as an expectant and excited young student.

Archmage Crumble felt a little too silly as a character, both proclaiming that an ice cream dispenser is better than some kind of more serious magical purpose, and not really acknowledging that Dilby just skipped class to race over to see what the monolith was. Without some kind of backstory or understanding of the relationship of these two characters, Crumble seemed a little ridiculous and it would benefit the story to have him more serious in one or more facets (e.g., he calls Dilby out on skipping class, he doesn't pretend that the ice cream dispenser is better magic than a summoning artifact, etc.) so that the amusement of the moment isn't outweighed by the silliness of his character.

Overall, this was a fun and entertaining flash fiction story. Well done!