The magnetic and electrical properties of ferromagentic∕superconducting∕ferromagnetic trilayers as a function of the thickness of the superconducting (SC) layer (between 5 and 15 monolayers) were measured. La2∕3Ca1∕3MnO3∕YBa2Cu3O7−δ∕La2∕3Ca1∕3MnO3 trilayered films were fabricated in situ on (001) SrTiO3 single-crystal substrates using dc sputtering with high oxygen pressures (3.5mbar). The crystalline quality of the trilayers was analyzed by x-ray diffraction. Transport and magnetic measurements revealed a weak dependence of the ferromagnet’s (FMs) Curie temperature TFMC and the FM magnetization on the thickness of the SC layer, and a strong dependence of the superconducting transition temperature TC.