Because now and then I get some emails with questions about Dehkhoda, which makes me happy, I want to answer the most asked ones.
Of course you can still write me mails.

What kind of courses does Dehkhoda offer?
Would you recommend studying at Dehkhoda?
How can I register?
What kind of accomodation exit?
Is there a canteen in the institut?
How much are food and other costs?
What about internet and telephones?
What is restricted?
How should I behave towards women?

What kind of courses does Dehkhoda offer?

There are two kinds of courses at Dehkhoda: An intensive course and a normal course.
The intensive course lasts 6 weeks and you have lessons 5 days a week (Saturday to Wednesday) from 9am till 12am with 30min break. When a course is finished you have one week of holiday.
The normal course lasts 9 weeks is classes are in the afternoon from 3.30pm to 5.45pm on Saturday, Monday and Wednesday.
You can find the exact times on the website.

Would you recommend studying at Dehkhoda?

If you don’t have any knowledge of Farsi, the beginner courses are not wrong. You will be taught reading, writing and of course speaking. In addition to the courses you will get homework and you should also learn the vocabulary (after the first course I had 700 words).
They have books, but they are like the lessons in Persian language. The teachers know English, but not all pupils. That’s why Farsi is lingua franca.
In my opinion this makes the comprehension of the grammar quite complicated and you should buy a grammar book in your own language (I should have done so, but didn’t).
Other issue is that Iranians with dual citizenship and Arabs also visit the beginner courses, but only to learn how to write. They can perfectly talk, the Arabs at least better than beginners, so it can be really hard for “real” beginners in mixed classes.
The pace is high and if you don’t study enough, it’s your problem. At least the teachers don’t align the pace with the best ones either.
I would, now that I can somehow speak and write and know where my weaknesses are, not attend Dehkhoda again. I believe that studying by myself, having contact with Iranians, following the media, reading books and writing little essays is more efficent.

How can I register?

I started in January 2015 and registered in September 2014. On the website is written you should register 3 months in advance.
You need to fill several forms:

• Visa Application form
• The data page and signature page of your passport
• Registration Form
• (not mandatory) A copy of your graduation certificate or current student ID card

It seems you can apply online: http://icps.ut.ac.ir/Dehkhoda_e/application.php
When some documents are missing, you will quickly receive a mail. When you have questions, they are most likely ignored and never answered.
I got my letter of acceptance one month before my course started.

What kind of accomodation exit?

There are different dormitories and the situation has most likely change since I left.
Students who come for the first time (and are not Chinese) are usually put in the Velenjak dormitory. If you want to change your dorm, I strongly recommend you to ask as quick as possible.
The first course I stayed in Velenjak (offical Danesh Pazhuhan Dormitory):

• Direct bus connection (20-25min, 5000Rial) to Dehkhoda, on foot about 1h
• In the North of Tehran, the wealthy part
• In the evening not much is going on outside and it takes at least 90min to the centre. But it’s very close to the “Roof of Tehran” (Bam-e Tehran). It’s very beautiful there and also good for running.
• The rooms are cleaned once a week
• There are single apartments
• Men and women live in the same building but on different floors
• Officially there’s some kind of curfew and a doorman. But I never had problems coming back at 2am, leaving at midnight or 4am.
• It’s kind of expensive – you find the prices here (Danesh Pazhuhan dormitory of Shahid Beheshti University), but I cannot tell if they are up-to-date
• There’s one washing machine and washing costs 50.000 Rials
• Mostly people who are not Chinese or “brown” are living there (sounds racist, but it’s the reality=
• 1GB of free internet

From the second course on I stay near Enghelab square (Tehran University Dormitory, Mr. Zanguyi):

• About 1h-1:30h with public transport to Dehkhoda with BRT (Bus Rapid Transport; with metrocard about 3000 Rial or 7000 Rial, if you change in Parkway and don’t walk),
  20-40min with shared taxi (30 000 Rial)
• Directly in the centre
• Supermarkets, grocery stores, cafés, restaurants and snack bars are all very near
• Great metro and bus connection (the BRT bus is running 24/7)
• You can still go out at 11pm to buy a burger or falafel
• Near Laleh Park, which is refreshingly nice
• No doorman, you can leave and come back as you want
• No internet
• Much! cheaper than Velenjak – Prices (Tehran university dormitory)
• A 4 story building with one apartment per floor. Each has 3 sleeping rooms (one without windows) with 2 beds. There is one bathroom and another toilet, a kitchen and relatively big eating room
• You can live in the room alone for another 1.5mio Rial
• When I was there, there was no washing machine, we had to clean ourselves, we didn’t have a vacuum cleaner (if it’s still like this, don’t pay the rent) and sometimes we needed to heat with the gas stove
• Roof terrace, from which you can see Damavand if there’s not too much smog
• The landlord, Mr. Zanguyi, is not very committed, you should get on his nerves very strong if you want something and threaten to not pay the rent

Conclusion:
I liked it in Enghelab way more. You are everyway within an hour, my Iranian friends lived all nearby, you see more from the daily Iranian life and despite all disadvantages the price-performance-ratio is unbeatable.
On the other hand I had roommates who didn’t like cleaning and I didn’t accept to clean everything myself. So you should be lucky or take action.

There is also another dormitory, in North Amir-Abad. I haven’t been there, but heard, it’s not good.

Some students also lived with their Iranian friends, but it’s not legal.

Is there a canteen in the institut?

How much are food and other costs?

There’s no canteen only a cafeteria in Dehkhoda where you can buy instant food and snacks. But in the neighnour building there’s a nice Italian restaurant and a café with nice icecream.
I didn’t live like a king in Iran, cooked myself most of the time and rarely went out eating.
Here some prices:
Restaurants, cafés (centre):

Falafel 25.000 Rial (0,60€)
Hamburger 30.000 Rial (0,75€)
Kebab 80.000-160.000 Rial (2-4€)
Ash 50.000 Rial (1,25€)
Dish in restaurant ca. 200.000 Rial (5€)
Coffee 100.000 Rial (2,50€)
Milkshake 140.000 Rial (3,25€)

And for groceries (centre, per kg) !Be careful, go to different shops in the neighbourhood, because the prices can vary very much (sometimes double)!:

• Tomatoes 15.000 Rial (0,37€)
• Onions 10.000 Rial (0,25€)
• Potatoes 12.000 Rial (0,30€)
• Zucchini/Courgette, Aubergine 30.000 Rial (0,75€)
• Rice 60.000 Rial (1,50€)
• 500g pasta 20.000 Rial (0,50€)
• Bread Lavash 8,000 (0,20€), Sanggak 15.000 Rial (0,37€)
• Dough (like Ayran/Kefir) 28.000 Rial (0,70€)
• Oranges 55.000 Rial (1,28)
• Apples 50.000 Rial (1,25€)
• Pomegranate 60.000 Rial (1,50€)

The prices are ALWAYS – apart from fruits and stuff – printed on the products, so you should not be able being cheated.

What about internet and telephones?

I bought an Irancell SIM card and 50GB mobile internet for 3 months (750.000 Rial, 17,50€). The speed ranged from 0 (5% of the time) to 1MB/s.
Costs for calling are low. You can call landline in most countries for 3 Cents/min.
Facebook, Twitter and other websites are blocked, so you need VPN or an antifilter. I used the one of my university and for my phone Psiphone.
Since you will often be asked for your number, it may be useful to get a second shitty phone with another number, if you don’t want to receive calls at 3am.

What is restricted?

Foreigners can move quite freely. You are quickly the centre of attention, being stared at and often talked to – on the bus, in the metro and on the street.
Although you’ll learn Persian I advise you to pretend you don’t understand anything when you have some problems with police: They usually don’t speak English and from my exprience give up quickly.
The rules in Dehkhoda are that you only travel with some paper. I did it once and then, like most students, never again.
Just use common sense; with being open, streching rules an intelligent way and curiosity you will have a great time in Iran.

How should I behave towards women?

With respect maybe?
Of course it’s not a problem to look at the Iranian beauties, chat with them or take pictures with them, at least in big cities. You will notice how they react to foreigners soon enough. There’s really no reason to be scared.
Rarely it happend that women whom I asked for some directions turned away or passed quickly with a strange facial express, but this is really an exception.