I have been teaching Sr High Sunday School for 18 years. One thing I have learned is that teens know very little about Jesus, theology and sin. A few weeks ago, I taught the passage about “If your eye offends you, pluck it out” and they were aghast that Jesus would say such a thing.
We cannot know if someone is sincere which is why we shouldn’t assume the “sinner’s prayer” has accomplished its mission. One thing I like about Methodism is that we kinda assume that Justification comes after Prevenient Grace. God seeks and woos the sinner into a relationship. It doesn’t just happen. It’s part of His divine purpose.
We don’t tell them about Christ. We tell them about what Christ has done for us. They cannot argue with that.
A Christ that just made you into nicer people might still not be anything more than, say, a Plato or a Freud.
Giving Him His full divine props is absolutely necessary — and generally in Baptist circles, parents WILL teach the children about the person of Christ.