So the fields in structs are marked as uncovered, even if you use selectors to access them.
After running the definitions, name and grade are marked as uncovered. I'm pretty sure this is a regression of some sort.
I think there must be something more to reproduce; I'm seeing no halloween colors with just the struct definition in both the menu-based BSL and in #lang htdp/bsl.
I just reproduced, but then I chose BSL from the language menu and it went away. When I went back to #lang htdp/bsl it didn't happen again.
I'll give it a try with a fresh install and see if maybe choosing Language > BSL before you try #lang htdp/bsl consistently fixes it, and not doing so causes it.
It may be some settings in the language dialog are relevant, maybe? ... just a shot in the dark.