  We present time resolved CCD photometry of 15 cataclysmic variables (CVs)
identified by the Sloan Digital Sky Survey (SDSS). The data were obtained as
part of the 2004/05 International Time Programme on La Palma. We discuss the
morphology of the light curves and the CV subtypes and give accurate orbital
periods for 11 systems. Nine systems are found below the 2-3h orbital period
gap, of which five have periods within a few minutes of the ~80min minimum
orbital period. One system each is found within and above the gap. This
confirms the previously noted trend for a large fraction of short-period
systems among the SDSS CVs. Objects of particular interest are SDSSJ0901+4809
and SDSSJ1250+6655 which are deeply eclipsing. SDSSJ0854+3905 is a polar with
an extremely modulated light curve, which is likely due to a mixture of
cyclotron beaming and eclipses of the accretion region by the white dwarf. One
out of five systems with white-dwarf dominated optical spectra exhibits
non-radial pulsations.
