Youngs was used as a second-half replacement against Scotland after appearing in the previous victories over Wales (28-15), Italy (22-13) and France (24-6), the latter in front of a 20,000 capacity crowd in Grenoble.
Noah Cato scored twice against the Scots to take his tally to five tries in four internationals this season with Seb Stegmann, Hugo Ellis, Joe Simpson and Matthew Cox also touching down.
Youngs was introduced in the 65th minute, by which time England were down to 14 men after lock Ben Thomas had been sent off.
Scotland U20: Murray Allan (Loughborough Univ); Lee Jones (Selkirk), Chris Kinloch (Edinburgh Acad), Steven Wilson (Dundee HSFP), Tom Bury (Boroughmuir); Ruaridh Jackson (Glasgow Hawks), Ross Samson (Newcastle Falcons); Gary Strain (Glasgow Hawks), Fraser Brown (Biggar), Lewis Niven (Edinburgh Acad), Neale Patrick (Dunfermline), Josh Brown (Bristol), Fraser McKenzie (Heriot’s), Lewis Calder (Newcastle Falcons, captain), Jonny Baird (Watsonians).
Replacements: Adrian Duncan (Stewart’s-Melville FP) for Brown 50, Angus Dixon (Aberdeen Grammar), Craig Simmonds (Heriot’s) for Patrick 55, Steven Burton (Currie) for Baird 65, Matthew Heeks (London Scottish) for Samson 72, James Murray (Leeds Carnegie & Edinburgh Acad) for Jackson 78, Paul Loudon (Durham Univ) for Kinloch 50.
England U20: Noah Cato (Saracens); Seb Stegmann (Harlequins), Luke Eves (Bristol Rugby), Alex Goode (Saracens), Mark Odejobi (London Wasps); Rob Miller (Newcastle Falcons), Joe Simpson (London Wasps); Nathan Catt (Bath Rugby), Joe Gray (Northampton Saints), Alex Corbisiero (London Irish), Ben Thomas (Saracens), Scott Hobson (Cornish Pirates), Jon Fisher (London Irish), Matt Cox (Worcester Warriors), Hugo Ellis (London Wasps, captain).
Replacements: Scott Freer (Leeds Carnegie) for Gray 55, Billy Moss (Bath Rugby) for Corbisiero 55, Graham Kitchener (Worcester Warriors) for Cox 65, Tom Sargeant (Harlequins) for Hobson 75, Ben Youngs (Leicester Tigers) for Simpson 65, Greg King (Worcester Warriors) for Goode 75, John Brake (Northampton Saints) for Stegmann 75.
