It's Wednesday, that day of the week when the Catholic kids go to catechism and the Jewish kids go to Hebrew school. As the lone Presbyterian in school, Holling has to perform a variety of tedious tasks while all the other students are away.
One of these tasks involves cleaning out the cage of the two rats, Caliban and Sycorax, named after characters from The Tempest, by William Shakespeare. Unfortunately it all goes wrong as the two rats manage to escape from their cage after Holling's finished cleaning it. What happened is that he got distracted by Mrs. Baker and, during that momentary lapse of concentration, Caliban and Sycorax made good their escape.
Mrs. Baker immediately instructs Holling to go and fetch Mr. Vendleri. He does so, jumping from desk to desk so as not to have the rats run across his feet again. When Mr. Vendleri arrives, he immediately takes stock of the situation before calmly going to the supply closet to fetch a shovel and two brooms.
Holling and Mrs. Baker are to flush out the rats with the brooms and, once they appear, Mr. Vendleri will scoop them up with a shovel. But the best laid plans often go wrong, and on this occasion, the two rats manage to evade capture as they climb into the radiators.