Beckett, on loan from Sheffield United, curled a low shot past keeper Bradley Jones from 18 yards following Chris Brandon's cheeky back heel only one minute and 21 seconds into the contest.
It is the fourth straight game in which Beckett has scored against Blackpool and the third time he has netted against the Seasiders this season - he scored a double for Stockport at Bloomfield Road before joining the Blades.
Defeat ended Blackpool's three-match winning run and leaves them looking nervously over their shoulders after working hard to escape the drop zone in recent weeks.
But the visitors only had themselves to blame against a Huddersfield side featuring eight academy products aged 21 or under, including 4 teenagers, who were later reduced to 10 men following Brandon's dismissal for bringing down Keith Southern on 57 minutes.
John Murphy had an equaliser ruled out for being marginally offside while Town defender David Mirfin headed Danny Coid's goalbound effort off the line in the closing stages.
Earlier, Blackpool had notched up six corners in the opening 15 minutes without ever testing keeper Paul Rachubka.
And the margin of defeat could have been greater had Beckett connected with a John McAliskey's low cross from the right on 26 minutes.
McAliskey also missed a second-half penalty, awarded on 63 minutes when he was pulled down by Peter Clarke in the box.
The 20-year-old striker scuffed a tame effort that Jones saved easily.
Blackpool threw everything at the home side and late on in the vain search for an equaliser even indulged in 'unsporting' tactics such was their desperation.
Seasiders' substitute Rick Wellens played on in stoppage time after Town defender Nathan Clarke knocked the ball out of play to allow two injured players to receive treatment.
But the visitors failed to capitalise on Wellens' quick thrown in to Murphy while the Terriers were temporarily down to nine men.