Tim Visser, Matt Scott and Sean Lamont also crossed the whitewash for the hosts as Scotland cruised to their biggest Six Nations win ever.
England Under 20s suffered defeat by the narrowest of margins against Ireland in Athlone, going down 16-15 after a late try from wing Rory Scholes and pressure conversion by centre Tom Daly.
The visitors were down to 14 men for the majority of the game when flanker Ross Moriarty was shown a straight red card after a dangerous tackle on Ireland scrum half Luke McGrath.
Fly-half Henry Slade scored all of England's points with five penalties from five, but it wasn't enough in front of a strong partisan crowd.
It was England who got the first points on the board through the boot of the Exeter Chiefs man, who punished Ireland for an infringement at the breakdown.
Daly levelled up with a penalty after Moriarty had been sent off. But England showed resolve and regained the lead with 28 minutes played, Slade again converting. He added his third penalty five minutes later to make it 9-3 at the break.
Ireland came out firing in the second-half and reduced the deficit to three points early on as Daly scored his second penalty of the night.
With 50 minutes played, England's determination earned them a fourth penalty of the night, Slade again converting the kick.
With England 12-6 up, Ireland were reduced to 14 men when kicker Daly was sent to the sin-bin for playing the ball off his feet, Slade added three points from the resulting penalty with his metronomic left boot.
Minutes later and it was England with the man advantage as full back Robbie Henshaw followed Daly to the sin-bin for a dangerous tackle on opposite number Howard.
Ireland continued to apply pressure though and wing Scholes scored the hosts third penalty to make it 15-9.
And it wasn't long before both sides had 13 men on the field after England lock Elliott Stooke was sent to the bin for pulling down a maul.
With ten minutes to play Ireland started to exploit their two man advantage and, after some steady build-up play, the ball eventually found its way to Scholes who dived over in the corner.
The try made the score 15-14 to England, but from a difficult angle the impressive Daly converted and Ireland held out to record their first Six Nations win over England since 2010.
England Under 20s now have a two-week break before facing France at Sixways on Saturday 23 February (Kick-off 3pm).
Tickets for the clash are available from the Warriors Box Office now. Adult tickets are £12 and Concessions (Juniors, Students, OAPs) are £6. A selection of Gold tickets are also available for £17.50. For more information call the Warriors Box office on 01905 454183.