I'm not a native english speaker, but shouldn't "I, too" be accepted as well?
Typically (though maybe not strictly) you can only say "I too" in a complete sentence. For example. "I too see the dog." or the famous, "I too like to live dangerously." http://knowyourmeme.com/memes/i-too-like-to-live-dangerously
If you are giving a simple response, however, you would say "Me too." This is a peculiarity of English that I never understood, but nominative (subject) pronouns cannot exist without a verb in modern English.
Incorrect → Correct
I too → Me too
He/She too → Him/Her too
We too → Us too
They too → Them too
I wouldn't say that it's incorrect to say I too, though. Originally, I too was the correct form of an implied sentence by omission, but because of the grammaticalisation of the objective forms as acceptable pronouns for certain constructions, the objective forms like me too and it's me became grammatical. That's not to say that using the subjective forms are no longer grammatical, just that they now have a pedantic register when not in a complete sentence. So it should be
Pedantic or formal register/casual
I guess I'm super late on this, but "I too" and "me too" are both correct, it just depends on what the rest of the sentence is. "Me too" could be short for "The same goes for me too," or you could say "I too" as in "I too agree with this." Most people don't seem to understand the practical differences between "me" and "I", though. My favorite example of an incorrect use of the word "me" is "He can run as far as me." In other words, "He can run the distance between me and him."
I wonder if the sentence be like, "mij ook."? I know that it's part of possession. But is it relevant? :D
I must be honest sometimes it drives me mad, 'I also' and 'Me to' please I know why but I am trying to learn Dutch not get corrected by grammar police, please duolingo stop being so pedantic, I think if you give the meaning in English that should be good enough, it should not have to be 100% grammatically correct?
All accepted answers are manually added to the database by volunteers. It's difficult enough to add all correct answers. If we had to anticipate grammatical errors and add those too, our job would be near impossible.