Songs of Worship

I was looking to prepare some spiritual songs for the children in Sunday school. I am having a hard time finding nice songs for children in English—something like the Arabic ones that we learned when we were growing up (e.g., 3an2ood 3enab, etc.).  

I see a lot of resources on some children's songs that are very nice, but I am concerned that they did not originate by the Coptic Church (e.g., originated from a Methodist, Baptist, etc. church in the U.S.).  I screened some of them to see if there would be any hidden meanings that are unorthodox, but even so, I am worried that if we teach them these songs and they become familiar with them, then if they hear the song outside of the church that it would be familiar to their ears, and then they would feel that it is permitted to go to that other church because we share the same songs, etc.

Am I over thinking it? I am comparing this to some songs that we learned when we were growing up that are protestant (e.g., rambo fel madrassa). If I go to one of those "concerts" by the protestant community, I would feel familiar with them and maybe if I were to be invited by them to join their meetings, I would not feel like it is a big deal.  That is what I am trying to avoid.

These children are around 8-9 years old. Maybe this would be more dangerous in the teenager age when they can actually go to other churches and be lead to attend there, but I am not sure.