The Magpies, who crushed Darlington in midweek, claimed five for the sixth time this season in front of their biggest crowd at Meadow Lane, who later saw the champions get their hands on the League Two trophy.
Graeme Lee headed in Ben Davies' corner to break the deadlock, before Lee Hughes lashed in another 15 seconds later after collecting Davies' long ball.
Lee Ridley then hacked Craig Westcarr's attempt off the line, before things went from bad to worse for the the Robins.
Davies' 25-yard free-kick deceived goalkeeper Scott Brown to go straight in, before the division's leading marksman Hughes made it 4-0. curling into the far corner for his 30th league goal of the season after chasing down Stephen Hunt's through-ball.
An overwhelmed Cheltenham just had snapshots from Matt Thornhill and Michael Pook to shout about but conceded a fifth when Luke Rodgers converted Westcarr's cross late on.
It was exhibition football at times for the hosts, who claimed a sixth straight home victory before parading their newly acquired silverware post-match.