Pale boy. 面色苍白的小孩儿。

一个小孩儿来到了学校,更面色（or 脸色）比平常更加苍白比平常。
老师问他：发生了什么？为什么你的脸色这么苍白？
小孩人说：没什么发生什么了。
我母亲只洗了我。（我母亲生病了，我照顾她 or 我母亲打了我）

One boy came to the school very more pale than usual.
Teacher asked him: What's up? Why you so pale?
Boy answered: Nothing happened. Just my mom washed me.

PS：The last sentence, I can't understand it.so I only  guess..

A Pale Faced Boy. 面色苍白的小孩儿。

一个小孩儿来回到了学校, 更面色苍白比平常比平时的臉色更非常蒼白。
老师问他：发生了什么事？为什么你这么苍白？
小孩回答人说：没什么发生了。只是 我母亲給只洗了我洗了臉。

One boy came to the school looking very more paler than usual.
Teacher asked him: What's wrongup? Why are you looking so pale?
Boy answered: Nothing happened. Just My mom just washed me.

Haha!

Pale boy. 面色脸色苍白的小孩儿。

一个小孩儿来到了学校，更面色苍白比平常他的脸色比平常更苍白。
老师问他：发生了什么事情/怎么了？为什么你的脸色这么苍白？
小孩人说：没什么发生了没发生什么/什么都没发生。

我母亲只洗了我。 

One boy came to the school very more pale than usual.
Teacher asked him: What's up? Why you so pale?
Boy answered: Nothing happened. Just my mom washed me.

I don't really understand what do you mean the last sentence  "Just my mom washed me".

So I cannot give my advice about it.

I am not an expert in Chinese language, so I will skip the Chinese part and go straight to the English part of this entry.

One A little boy came to the school very a lot more paler than usual.
His teacher asked him: What's up? Why are you so pale?
The boy answered: Nothing happened. Only Just my mom washed gave me a bath.