Abstract: A device (2) for training and stimulation of dogs or children, which device (2) comprises a number of elements (6, 6?, 8, 8?, 74, 76, 78, 80, 88, 88?, 90, 90?) configured to be locked and thereby fix and at least partly hide a number of tidbits (4, 4?, 4?, 4?), wherein the device (2) has activation members (12, 12?, 12?, 12??, 14, 16, 26) for opening/detachment of the elements (6, 6?, 8, 8?, 74, 76, 78, 80, 88, 88?, 90, 90?). The elements (6, 6?, 8, 8?, 74, 76, 78, 80, 88, 88?, 90, 90?) prevent one or more of the other elements (6, 6?, 8, 8?, 74, 76, 78, 80, 88, 88?, 90, 90?) from being opened/detached in such a manner that a first element (8?) is required to be opened/detached in order to open/detach another element (8).