Presumably the direct route has to be 150nm? Otherwise you could do lots of circuits as part of your QXC. However, JAR-FCL 1.125 doesn't actually say it needs to be direct
Doubt it will matter unless someone at the CAA is having a really bad day (although rustle is right - NavBox reckons it's 144nm direct) but bloomin' 'eck, your school should be smart enough to send you on a valid route. Maybe you should tell someone before somebody gets their licence application returned...