Turtles and tortoises that have been in captivity should NOT be released into the wild! They carry diseases, some that the common person and non-specialist vets, cannot easily detect, but which can devastate wild populations. Plus, you cannot expect that they will do well in the area where you release them. If you no longer want these pets and want them to survive and not potentially endanger their lives and the lives of other turtles, you should find a turtle rescue organization. Go online and I'm sure you can find one. This could be a great teaching of responsibility moment for your daughter.