We have started using the Charlotte Mason Bible memory verse system and is just what we needed. We have often taught Petra a memory verse, only to forget to go back to it at a later date so that she retains it.
The Bible memory verse system by Charlotte Mason is simple and effective. You cycle through all memory verses at least monthly, and do the ones you are learning, or recently learned on a more regularly basis. And all it takes are some 3×5 index cards and a box for them.
You can check it out here.
Here they are reciting some of their verses. You will notice they can’t stand still…but they still know what they’ve learned. =)