  The central area of the Sculptor dwarf galaxy was surveyed for variable stars
as a side-program of the OGLE project. Light curves in the V band were obtained
for 226 RR Lyr stars and for 3 anomalous cepheids. One previously unknown
anomalous cepheid was identified. We discovered also two variables located at
the tip of the red giant branch of Sculptor. Out of 226 RR Lyr variables 135
were classified as RRab, 88 as RRc and 2 as RRd. Distribution of periods for
RRab stars shows a sharp cut-off at P=0.475 days. This implies that the bulk of
Sculptor RR Lyr stars has metallicity [Fe/H]\leq -1.7 on the Zinn-West scale.
The average V magnitudes of RRab variables are correlated with their periods.
This effect is most probably caused by the spread of metallicities exhibited by
variables. Based on the average V magnitudes of RR Lyr stars the apparent
distance modulus of Sculptor was determined at (m-M)_{V}=19.71. The
color-magnitude diagram of Sculptor reaching V\approx 21.4 and I\approx 20.6 is
presented. The observed width of the upper part of the red giant branch
indicates range of metallicities -2.2\leq [Fe/H]\leq -1.6 for the Sculptor
giants. The observed distribution of stars along the horizontal branch and
average value of metallicity imply that age of Sculptor is similar to ages of
the relatively young globular clusters from the outer galactic halo. The data
about RR Lyr variables in four nearby dwarf galaxies are summarized and
discussed briefly.
