Peter replied, Repent and be baptized, every one of you, in the name of Jesus Christ for the forgiveness of your sins.  And you will receive the gift of the Holy Spirit.  The promise is for you and your children and for all who are far off – for all whom the Lord our God will call.   – Acts 2:38-39

But what does it say? The word is near you; it is in your mouth and in your heart, that is, the word of faith we are proclaiming: That if you confess with your mouth, “Jesus is Lord”, and believe in your heart that God raised him from the dead, you will be saved.  For it is with your heart that you believe and are justified, and it is with your mouth that you confess and are saved.   – Romans 10:8 – 10

Ok, so salvation is for everyone, even the kids.  Don’t leave them out. 
And Jesus is Lord and I believe that God raised him from the dead.  It’s that simple.  It’s hard to live a Christian life, but it’s that simple – child like faith.  
Please don’t disregard a child when he or she says they have made a decision to follow God because we are to proclaim Christ to kids that they can believe in him too and what he has done for them, for all of us.
Just a thought.