Something

while(temp != NULL && temp->getDivisionNum() > divNum)
    {
        prev = temp;
        temp = temp->getNext();
    }

    newDiv->setNext(temp);

    if(prev == NULL)
    {
        head = newDiv;
        return exists = true;
    }
    else
    {
        prev->setNext(newDiv);
        return exists = true;
    }