“…Order of development of conservation concepts has been investigated with children who have different handicapping conditions and with non-handicapped children (Lister, Leach & Hull, 1987;Lister, Leach & McCombe, 1988;Lister, Leach & Wesencraft, 1988;Lister, Leach, McGraw & Simpson, 1989;Lister, Leach & O'Neill, 1989;Lister, Leach & Walsh, 1989;Lister, Leach & Hill, 1990). None of these investigations has included children with cerebral palsy.…”