Way back when I was a Cub Scout, for one year our Pack was chartered by a Catholic Church. I had been brought up in a family that generally attended a Baptist church. Being in NC, most of the boys in the pack were more than likely from some protestant denomination.
In many protestant denominations, communion is considered open to all who profess Christianity. In the Catholic church, they practice closed communion, where it can only be offered to those who follow their particular faith.
(I'm not going into the details of why here, but there are deeply held theological opinions on both sides as to why each church handles it the way it does.)
On Scout Sunday, all of us Cub Scouts were sitting there together, all in uniform, hopefully being well behaved. Anyway, when we got to the part of the service where it was time to receive communion, all the cub scouts lined up, not realizing that it was not open to all, as we had probably seen in our home churches. Our Den Leader who was Catholic had to grab us out of the line, and it was a little embarrassing to both us and her. I don't think it was ever explained well to us why we could not participate.
Anyway, my point of bringing this up, is that before you invite Scouts to participate in your own church's services, remember that you too may have some unique part of the service that the scouts and possibly their parents need to be made aware of. In that particular case, it was who was eligible for communion. At my current church, I had to make sure that all the parents knew what ages were welcome to go down to the Children's church part of the service, and where to get their kids after service was over.
Look over your own church service, and think about what things might need to be explained in advance to those who are visiting. That's probably a great rule for every Sunday, not just Scout Sunday.