I have a Trails End 25-35, and would say its anything but a kids gun. True, the kick is minimal, but shot placement must be perfect for a kid. The above recommendation for a 30-30 is sound. There is a 336 Spikehorn floating around on one of the forums for sale. I have a 6 year old son that shoots a 357. He routinely will shoot 125gr. bullet at about 1100fps for practice, and can easily handle the high velocity 180gr. cast bullet we use for pigs and deer. Granted, its only good to about 100 yards, but thats all the further he needs to be shooting. My girls, both 11 and 9 shot the 357 the other day and both did very well with it to 100 yards. Its a great gun to download and get experience with. When the time comes for taking game, its also up to the task. The 6 year old is big for his age, but I bought an old birch stock and cut it down. This is perhaps the most important thing I did.
Good Luck!