I don't know if it's the right thing for your church to do, but God does know, and the most important thing you and the other members of your church can do is to seek God's will about this matter.
On one hand, you're wise to be concerned about too much debt; occasionally I've known of churches whose ministry was seriously hampered because of unwise debt. God is not honored when a church or other ministry ignores sound business principles. The Bible says, "Let no debt remain outstanding, except the continuing debt to love one another" (Romans 13:8).
On the other hand, I'm thankful your church wants to reach out to young people - not only those in your church, but also others who need Christ or have no contact with a church. If we fail to reach the next generation for Christ, our churches will shrink, and our society will descend into moral and spiritual chaos. Jesus' command is clear: "Go into all the world and preach the gospel to all creation" (Mark 16:15).
Modern buildings may have their place, but even more important is a commitment to use them for God's glory. And that kind of commitment only comes from a deep love for Christ and a desire to serve Him. Is this true of you and others in your church? Never forget Jesus' promise: "But seek first his kingdom and his righteousness, and all these things will be given to you as well" (Matthew 6:33).