0800-0850         1^st period

0850-0910         cleaning time in the morning

0910-1000         2^nd period

1010-1100         3^rd period

1110-1200         4^th period

1200-1300         lunch break

1305-1355         5^th period

1405-1455         6^th period

1455-1510         cleaning time in the afternoon

1510-1600         7^th period

1610-1700         8^th period (if necessary)