Helping your childs mind grow

I have a four year old daughter.  An when it came time that my daughter started talking, I made sure people watch what they said around her.  I was once told that a childs mind is like a sponge an sure enough its true.  They absorb everything they hear an mock it.  Sure enough she did. 

Aleia was always very advanced for her age.  When she was a year old she was doing stuff two year olds should be doing.  I was very proud of her to say the least.   I had always made sure that she had educational toys.  Some how to teach her anything an everything she could learn from it.

Here she now 4 an it seems she has stopped wanting to learn.  At the age of 4 she should know numbers, letters an colors.  For awhile she knew a few, but as much as I hate to say this, she seems to be playing dumb. 

So I sit here an wonder if there is something wrong with her.  People tell me that in her own time she will learn this stuff, at her own pace.  But she gets to start PreK next year an she wants to go to school so bad, but I am afraid that they will say she won't qualify.

So I guess I am asking how do I get her to want to learn these things.  I have done everything from getting a PreK work book an call it her homework book, but she doesn't listen to the directions I give her.  I try an show her a color an tell  her to find objects in the house that are that color.  Counting I will take shells an have her count them, but done of these things seem to work.

I want to help her learn these things, I want to help her brain become the sponge it once was.

Any advice would be greatly appreciated.  Any personal experience or any known websites would help as well.