I can’t find the translation anywhere

I'm currently reading "Yotsubato!" but yotsuba keeps saying a word I can't understand and I can't find the translation anywhere.
Also its not clear enough to understand, maybe the manga scans are bad.
Its something like this:

かいっばい
or
かいっぱい
or something like that.

Can someone help?

Umm...
おなかいっぱい (I'm full.)
or
ダンボーがいっぱい (full of Danboard)
http://www.yotsuba10.com/movie.html

Or if you show that volume and page, someone can check it, thouh I have AzMangaDaiou only.(x_x;

Here is a link. Second panel

http://imageshack.com/a/img829/4139/g7vz.jpg

It's "すげえ"　and then, ひとかいっばいる　or sometihng like that, I know what hito means but whats next? I really cant find in the dictionaries I use.
Thanks in advance

人がいっぱいいる

Hito ga ippai iru

Literally, "There are a lot of people" or "It's full of people" usually used in the sense of "It's crowded" or "There's a big crowd."

Wow cute Yotsuba-to(-&)! lines :)

Not [か(ka)] 人[が(ga)]いっぱいいる is right.
This [が(ga)] is jyoshi[助詞].
http://en.wikipedia.org/wiki/Japanese_particles
Just you couldn't find pretty small "dakuten" part.
http://media.animevice.com/uploads/0/4479/327975-ga_2_super.png
You could read 学校[が]っこう part,right?
Just bad printing and bad font not rare case.

BTW, no reading Eng .ver?
http://www.mangahere.co/manga/yotsubato/c001/5.html

It's quite colloquial, but the "...ga" is a particle, which you should read up on :)

I wrote out the lines below, with some close-to-textbook expressions in parenthesis.

すげぇ〜！！（すごい） Awesome!
人が　いっぱい　いる！ There are many people!

きょうは　まつりか！？ Is today (some kind of) festival?

学校だ　学校 It's school, school (you know)
そういや　（そういえば）明日から　夏休みだなぁ
Come to think of it, from tomorrow it will be summer holidays.

Hello and really thanks for all the help.
It's true the dakuten was not clear in that panel, and I kept searching that for　か instead of が.
I'm self learning japanese and I decided to read an easy manga for practice.
Yes I could read the kanji for school.
Thanks everyone!