السلام عليكم مبتعثه شيكاغو ان شاء الله

Hi, I can't tell that much about Intrax, but what I know is that they are good for the speaking and listening part, also it's not an academic institute.
If you want my suggestion, if your English is not that good, study with them till you reach the Advance level or High intermediate, then transfer to ( ELA ) Depaul university, which is one of the best English Academy in Chicago.
About the weather, In April I would say it goes around the 60's F which very nice (( not that cold and not very hot )) we will only need to wear a sweater.
In the summer, it become very hot and hummed, around the 80's F especially in August, but sometimes it goes around the 70's which is very nice. The summer there is around 3 months, the city will also become crowded in the summer. Inshallah you will Enjoy it.
The winter, is very very cold and freezing. It starts on November and end by the end of March. The worst two months are January and February. it usually snows a lot and sometimes goes around -20 to -28 C, but the normal is between 3 to -3 C.
Chicago is famous for the Wind (( The windy City )) and that is what will make the winter even worse.
Be careful where to live, I'll write a list of the places that you should and must avoid:
1- Cicero
2- The south side from the 35th ST to the 97th ST
3-deep west of Chicago
4-Ridgeland
5-Austin
6- Pulaski
7-Kedzi (( the west side )) not sure about it

the rest Inshallah will be safe, but always ask about area before you move to.
Now, the transportation,
you can buy a monthly pass card for 86$ and the ride the train and the bus many times you want for one month.
There is 8 lines for the train (( Green, Blue, Red, Orange, Pink, Brown, Yellow, Purple)) m
1- Green Line: it runs from the early morning till around 11;30pm. from 9:30pm till 11:30pm it won't be safe to ride it alone, if you have to, always remember to set on the car behind the driver, and the train goes from Oak park to the deep south.

2- Blu Line, Goes from Oak park to O'HARE Airport. It runs 24 hours not that bad to ride it alone.

3- The red Line, goes from Howard where University of Loyola at, to the deep south. In the red line always ride on the first car and try not be on the train after Roosevelt station, where the real danger starts. It runs 24 hours.

4- Orange, I don't know where it's start, but I know it goes to Midway Airport, Also not safe at night and runs 24hours.

5- Pink, yellow, and Purple I don't know anything about them

6- Brown Line, it's very safe, and runs early in the morning around 5am till 2am.

I hope I've gave enough info about Chicago, and also sorry for writing in English cuz I don't have an Arabic Keyboard. Anyhow if you need more info don't you ever hesitate to ask.