Some success criteria you might consider including come from the G8 and G9 video specifications list.

(NB: These refer almost entirely to the technical success/quality of a video product and are not sufficient to achieve the 7-8 grade band in G10.)

720p (HD) or 1080p (Full HD)
Compositional Elements (esp. Rule of Thirds)
Good sound (inverse-square law/“the best zoom is your feet”)
Narrative (e.g: three-act)
Royalty-free music
Variety of shots
Steady shots (use monopod or tripod)
Continuity
Future-proof (no transitions, special effects, etc.)
Avoid backlighting (silhouetting)