I think the kids on the covers do look a lot like I picture the Animorphs. Definitely not exactly, but still a lot.
I agree with msteck that Marco looks young, but then, he was young
He was also very short, so it makes sense that a young kid would portray him. But at the same time, he was 13 or so in the beginning, so I assume he was 14 or 15 in #35, so I guess the kid kind of looks a little young.
I think the girl portraying Cassie on the cover of #4 is really good. She looks very young in my opinion and Cassie was only 12 or 13 (I think) then and probably looked a bit younger. When the Controllers find a pair of jeans from one of the Animorphs (not sure if that particular part was in #4, but I think so), they say they belong to a kid of age 10-12, which I assume can only be Cassie or Marco, since they were smaller than the others.
I agree about Rachel, too. She looks a lot like how I think Rachel would look.
The person looking the least like how I imagine them is probably Tobias (or the human Ax). I do NOT think the kid on #13 looks anything like I picture Tobias. Then the kid on #43 is okay, but much too young. But then it's the same kid on the other covers of the Tobias books, right? Maybe not, but it looks that way to me.
I quite like that kid, even though his hair is supposed to be lighter and messier
Jake is okay on the first cover, but other than that... Nah.
Do you know how many of the covers have the same kids portraying the Animorphs?
Oh, and about the TV show. None of them look like how I've pictured them. First of all, the actors were too old and their characters were too old too (the characters were all 16, but the Animorphs were not that old when the whole thing started).
Shawn was 19, Boris was 18, Nadia & Paulo were 20 and Christopher was 21. Brooke was the only one who was 16, like their characters (and even that was too old, since the Animorphs were actually supposed to be like 13 in the beginning).
Second:
* Brooke is a great actress and she's very pretty, but she's way too soft to play Rachel. And she has brown eyes, while Rachel's supposed to have blue. She's also too short
* Shawn is also a good actor, but doesn't fit to play Jake at all, in my opinion. He definitely doesn't look serious enough and, well, enough like a leader or a general, if that makes any sense. He also doesn't have dark hair and brown eyes.
* Chris looks too "tough" to be Tobias. He's also too tall and his hair is too dark.
* Nadia's very pretty, but her hair is too long
Her skin is too light and she's too tall. Otherwise she's definitely sweet enough to play Cassie
* I love Boris, but not as Marco. I can't explain why exactly, apart from being too tall, but he just does not look like Marco to me. And sure, they made his character funny, but not like Marco.
* Paulo... Sorry, he was just all wrong for Ax.
Man, do I complain a lot!
The actors and actresses of the TV show were great. They just didn't fit to play the Animorphs, in my opinion
On the other hand, I don't think I would've been very satisfied no matter who played them
