Pros
American Language School, or ALS or IB Japan, is not te worst company out there but ther's more a testament to how bad some companies are than anything in favor of the school itself. However, some things they do well are;
Good, helpful managers who generally speak good English
Two weeks off for summer and two weeks off for winter
A relatively easy job.
Cons
The bad things? Oh, where to start. First off, don't be fooled by their pitch. A lot of things they try to sell as good things in the contract actually are really bad. For instance;
1.5 year contract. They sell it as more job security but actually it's an excuse to make you work half a year longer without having to give you a raise.
Sick days of SPA days as they are called. They say that if you don't take any time off you will not have to work certain weeks. This is not true. You will not teach classes but you will be doing administrative work if you did not take any sick days.
No national holidays. Unlike ECC, and other bigger companies you will work during national holidays.
Very disorganised head office. They take forever to reply to emails.
They force you to live in their own housing and profit off you by selling you the housing at almost twice the market price.
Very little support after training.
May spring unpaid work on you suddenly. This happened to me several times in which I had to give up my Sundays to work without being paid for it. And you cannot say no.