Up front, Rockwell College's Sean O'Connor comes in for Peter Claffey in the second row, and Johnny Guy from St. Andrew's replaces the injured Charlie Cregan at openside flanker.
Newbridge's Jimmy O'Brien comes in at out-half with Matthew Gilsenan switching to inside centre and Colm Mulcahy wearing the number 13 jersey. Paul Kiernan is the player to make way.
There is a further switch on the right wing where St. Andrew's student Jordan Larmour, who impressed as a second half replacement against the Georgians, starts at the expense of Calvin Nash.
The three try scorers from the win over Georgia - Jack Power, Jacob Stockdale (2) and Will Connors - are retained.
The semi-finals are scheduled to be streamed live here on Tuesday. England and Wales compete in the other last-four tie, with the Championship decider taking place in Wronki next Saturday.
The Irish squad is coached by Noel McNamara (head coach), Mark Butler (backs coach), Brian Robinson (forwards coach) and Paul McCarthy (scrum coach).
Click here for the tournament fixtures/results.
IRELAND UNDER-18 SCHOOLS Team & Replacements (v France, FIRA/AER Under-18 European Championship Semi-Final, Plewiska, Poland, Tuesday, April 15, kick-off 4pm local time/3pm Irish time):
15. Jack Power (Blackrock College/Leinster)
14. Jordan Larmour (St. Andrew's College/Leinster)
13. Colm Mulcahy (Clongowes Wood College/Leinster)
12. Matthew Gilsenan (St. Michael's College/Leinster)
11. Jacob Stockdale (Wallace High School/Ulster)
10. Jimmy O'Brien (Newbridge College/Leinster)
9. Rowan Osborne (Clongowes Wood College/Leinster)
1. Andrew Porter (St. Andrew's College/Leinster)
2. John Molony (Clongowes Wood College/Leinster)
3. Conan O'Donnell (Summerhill College/Connacht)
4. James Ryan (St. Michael's College/Leinster) (capt)
5. Sean O'Connor (Rockwell College/Munster)
6. Will Connors (Clongowes Wood College/Leinster)
7. Johnny Guy (St. Andrew's College/Leinster)
8. Max Deegan (St. Michael's Collge/Leinster)
16. Conor McIlmurray (Campbell College/Ulster)
17. Hugo Kean (Blackrock College/Leinster)
18. Conor Kenny (Garbally College/Connacht)
19. Peter Claffey (Garbally College/Connacht)
20. Greg Jones (St. Andrew's College/Leinster)
21. David Duggan (St. Michael's College/Leinster)
22. Paul Kiernan (Presentation Brothers Cork/Munster)
23. Oisin O'Meara (St. Michael's College/Leinster)
24. Alan McMahon (Rockwell College/Munster)
25. Calvin Nash (Crescent College Comprehensive/Munster)
Ireland Under-18 Schools Result/Fixtures -
IRELAND U-18 SCHOOLS 20 Georgia 10
Opalenica, Friday, April 11
IRELAND U-18 SCHOOLS v France
Tuesday, April 15
Plewiska, 4pm local time/3pm Irish time
IRELAND U-18 SCHOOLS v tbc
Saturday, April 19