How old is Did, Zim, Gaz and Tak? And what grade is Did and Gaz in skool? (EX-5th, 6th, ect.)

ok for dib im pretty sure e is in 7th since the creator said he's 12. I would of said 6th grade but then how does gaz go to the same school? So im pretty sure that dib is in 7th grade and gaz is in 6th grade. As for Zim, jhonen said he is 16 in irken years (169 earth years) and he is in 7th grade with dib. As for tak she would be younger than zim since she was still in training while zim had already been a military scentist/engineer and was an invader. So i can conclude that she is 13-14 and is in 7th grade with dib. So here's a review:

*Gaz: 11 (6th grade)
*Dib: 12 (7th grade)
*Tak: 13-14 (7th grade)
*Zim: 16 (7th grade)

Remember i have found this through watching and studying the invader zim characters over the last year. Hope this helps!

P.S. as an added bonus ill give you Invader Skoodge's age. He is 16 since he was in the same class as Zim as well as the two tallest would be 16 since they were in the same class.

I would judge Dib as being 11-12, and Gaz at around 9-10. Zim seems to be an adult (in irken years, at least, I don't know how this works). Dib is probably in 7th grade, and Gaz in 4th or 5th.

Dib is roughly 13, Gaz is 11 and as for Zim and Tak they're actually over 50 because in Tak, the hideous new girl, Tak says it was 50 years ago in a flashback and then she said something about she had to wait 70 years so Zim and Tak are definitely over 50

Me? I always thought Zim was around Dib's age. Like 7th grade. But jn Irken years, i know he's way older then 12-14. Gaz, im guessing she's somwhere around 5th gradd. Bur peopla are saying that Zim is like, 16. It surpised me when i read that