This package does not contain all files from upstream. E.g. below
/usr/share/openboard/library/applications the directories
ColorPicker.wgt and Calculator.wgt and many others are missing.

Those files are already missing in the git repository at
https://salsa.debian.org/debian-edu-pkg-team/openboard/-/tree/master?ref_type=heads.
So I assume something went wrong during import.

I'm referring to the package for Debian Trixie:
https://packages.debian.org/trixie/openboard-common

Martin

See the comment around line 60 of
https://salsa.debian.org/debian-edu-pkg-team/openboard/-/blob/master/debian/copyright

Thank you,
Jeremy Bícha