We present a new fluorescence microscopy technique that provides depth discrimination in thick tissue. The technique relies on a simple modification to a conventional wide-field microscope, and consists in illuminating the sample with a sequence of speckle patterns and displaying the RMS or the variance of the resultant sequence of fluorescent images. We demonstrate quasi-confocal optical sectioning with an axial resolution of 5 microns FWHM. The lateral resolution is identical to the widefield microscope, namely 0.6 micron FWHM. Images of a mouse brain are compared with standard wide-field images, demonstrating an efficient quasi-sectioning capacity in thick tissue throughout approximatively 100 microns depth. This is achieved because of the high contrast maintained by speckle in a scattering media.