A scheme is presented for preparing maximally entangled states among six modes. The scheme only utilizes weak cross-Kerr nonlinearity and momentum quadrature homodyne measurements on the probe mode of intense coherent light fields. It is relatively easy to generate Dicke states and W states of light fields in the scheme. It is not necessary that the cross-Kerr nonlinearity is very large, as long as the coherent light is bright enough. Therefore, this scheme is within the reach of current technology. In addition, only weak coherent light beams, with which single-photon sources have been replaced in the signal modes, are needed in the present scheme since it is difficult to realize single-photon sources in experiments.