The enlarged squad began training in earnest at the WRU's National Centre of Excellence this week with Lewis keen to consolidate some of the playing philosophies he has already put into place at regional and international level.
He said: "We put the coaching team in place back in the summer in order that they could get to work with identifying and observing players within the Regional Age Grade Championship, which has once again been invaluable in our selection process.
"The WRU Colleges League has also increased in importance with players such as Llandovery College's Dan Brooks performing so well for his college that he earned a place in the Ospreys Regional U18 side and is now part of our national training squad.
"Our philosophy as a National Academy, and in particular with the U16 and U18 age groups, is to encourage players to put pressure on the opposition with the ball in hand. We believe that being bold and creative must be encouraged but within the basic template of being comfortable with the ball in hand and maintaining possession through quick recycling of the ball and the use of space and width.
"The game of rugby is based on constant intelligent movement and our objective is to develop 'rugby bright' players. Once players reach the U20 stage of their development, there will be an emphasis on tactical thinking and decision making but at U16 and in particular U18 level, we are prioritising basic skills, and in particular keeping possession alive whenever possible in order to develop an attacking, quick tempo game to benefit Welsh rugby as a whole.
"We have worked closely with WRU performance coaches within the regions and there has certainly been a greater intent to play with ball in hand at regional age grade level this season, plus we have players within this season's national squad who were with us last season so I'm confident we will see some results of that strategy this season."
There are 13 players from the Blues and Scarlets regions within the training squad, with 10 Ospreys, five Dragons, two players from the North Wales Academy and one Exile in Ben Calder from Saracens.
Wales U18 training squad:
Forwards: Callum Mitchell (North Wales/ Llandrillo College / Colwyn Bay), Alex Jeffries (Dragons / Coleg Gwent / Newport), Bradley Davies (Scarlets / Coleg Sir Gar / Pontyberem), Ryan Elias (Scarlets / Bro Myrddin / Carmarthen Athletic), Torin Myhill (Scarlets / Coleg Sir Gar / Burry Port), Javan Sebastian (Scarlets / Queen Elizabeth High / Carmarthan Athletic), Harrison Walsh (Ospreys / Gower College / Mumbles), Rob Lewis (Blues / Coleg Morgannwg / St Peters), Liam Belcher (Blues / Porth County Community School / Treorchy), Dillon Lewis (Blues / Ysgol Gyfun Garth Olwg / Pontypridd), Josh Helps (Scarlets / Dyffryn Taf), Adam Williams (Ospreys / Olchfa Comp/ Swansea Uplands), Adam Beard (Ospreys / Neath College / Birchgrove), Rory Thornton (Ospreys / Gower College / Bonymaen), James Sheeky (Blues / Coleg Morgannwg / Glamorgan Wanderers), Michael Snook (Blues / Llanishen High / Llanishen), Oliver Griffiths (Dragons / Coleg Gwent / Crumlin), Josh Middleton (Scarlets / Glanymor / Kidwelly), Will Boyde (Scarlets / Coleg Sir Gar / Narberth), Jordan Collier (Ospreys / Neath Port Talbot Coll/ Tonmawr), Callum Davies (Ospreys / St Josephs / Tonmawr), Ollie Hitchings (Blues/ Cowbridge Comp / Glamorgan Wanderers), Matthew Marley (Blues / Radyr Comp / Pentyrch), Sam Parker (Blues / Whitchurch Comp / St Peters, Glamorgan Wanderers).
Backs: Ben Calder (Oaklands School/ Saracens), Gareth Rees (Scarlets / Coleg Sir Gar / Ammanford), Tom Williams (Blues / Treorchy Comp / Treorchy),Dan Brooks (Ospreys / Llandovery Coll/ Bonymaen), Angus O'Brien (Dragons / Caerleon Comp / Caerleon), Jack Maynard (Scarlets / Coleg Sir Gar), Luke Price (Ospreys / Maesydderwen / Abercrave), Daniel Jones (Scarlets / Queen Elizabeth / Carmarthen Quins),Cameron Hughes (North Wales / Rydal Penrhos School), Tyler Morgan (Dragons / Coleg Gwent / Caerleon), Craig Woodall (Scarlets / Amman Valley), Joe Thomas (Ospreys / Neath Port Talbot Coll / Morriston), Garin Smith (Blues / Pontypridd High / Pontypridd), Ashton Hewitt (Dragons / Caerleon Comp / Newport), Josh Adams (Scarlets / Coleg Sir Gar / Pontyberem), Dafydd Howells (Ospreys / Neath Port Talbot Coll / Abercrave), Ellis Wyn Benham (Blues / Ysgol Glantaf / St Josephs), James Whittingham (Blues / Cowbridge Comprehensive), Steffan Evans (Scarlets / Ysgol y Strade / Kidwelly), Aled Summerhill (Blues / Coleg Morgannwg)
Wales U18 home fixtures 2013:
St Helens, Swansea
Wales Under 18 v Leicester Under 18
Tuesday 12 February 14.30 (half term week)
Wales Under 18 v France Under 18
Sunday 24 February 14.30
Wales Under 18 v England Under 18
Sunday 10 March 14.30
Tickets adults £5, Under 16s free, tickets available from Swansea RFC and by calling 01792 424242