Max Morrison comes in for a first start of the festival at loosehead prop. Dan Casserly moves back to hooker from number 8, and Oliver Anderson continues at tighthead.
Dan Shellard is paired with Will Lockhart in the second row, and the forwards are completed by Ashton Young at blindside flanker, Jack Nesbitt at openside and Harry Jackaman, who will captain the side, at number eight.
The half-back pairing is made of Cameron Trayler at scrum-half, and Henry Widdowson starting at stand-off.
In the centres, Joe Taylor begins on the inside and is joined by Ben McDonald on the outside.
Glen Gammell returns and is selected at left wing, with Luca Mathieson on the right. Full-back Rory McHaffie completes the starting team.
Scotland U18 Men team to play Spain U18 at Le Stade Darragon tomorrow (kick off 15.15pm BST) – live on the Scottish Rugby YouTube channel
15. Rory McHaffie
14. Luca Mathieson
13. Ben McDonald
12. Joe Taylor
11. Glen Gammell
10. Henry Widdowson
9. Cameron Trayler
1. Max Morrison
2. Dan Casserly
3. Oliver Anderson
4. Dan Shellard
5. Will Lockhart
6. Ashton Young
7. Jack Nesbitt
8. Harry Jackaman CAPTAIN
Replacements
16. Jack Utterson
17. Logan Hendrie
18. Jackson Rennie
19. Christian Lindsay
20. Harvey Preston
21. Gregor Johnston
22. Lloyd Moncrieff
23. Ben MacDougall
24. Harry Clark
25. Will Corbett
26. David Barrie