I bought Jem Golds for both my grandchildren
It's a great little machine
I used one myself for workshops, retreats etc til I upgraded to the Jem Platinum (just had to have the needle-down)

I agree on speed control....GD started out when only 2. I would let her guide fabric learning where and how to place fingers.....By time she was five she had made her own quilt and quilted it on a mid arm machine. Be mindful of their size and accordingly set her up with the proper height chair and table...Machine GD uses is a Brother..At this point (10 yrs old) she has temporairly lost interest in sewing and now into basketball and good grades...next I suppose will be boys.lol

I think a great used machine with just the basic stitches is a good start. I recently gave my niece an older Viking that had very basics , non- computerized.. and its perfect for her needs.
Check the local Sew and Vac or dealers as they take in great used machines and can offer some kind of warrenty. Plus you can test drive it prior to purchase , the cheaper machines sold at Jo'Anns or Walmart in the box , do not allow you to test drive.
I tought several beginners who pruchased very inexpensive machines and had lots of frustration , but when they sewed on one of my older machines they loved sewing.
I found one of the biggest issues with younger beginner sewers is they seem to want to pull the fabric through the machine . I make them use scrap fabric and sit back in the chair and see what happens when they let the machine just take in the fabric. I tell them they are doing it incorrectly if there hands are more than 1 - 2 inches in front of the needle. Once they really "get"that the machine will take in the fabric , the issue of getting finger in the needle is lessened.

It seems like the toy machines that I've seen have 2 speeds - fast and off. I would be more afraid of those machines than I would with a more control-able adult model. Make sure to tell her if she doesn't watch and take care the needle will go through her finger and it will hurt - a lot! Maybe let her see how sharp a needle is(off machine of course). I think you're doing great teaching her at a young age.

I was in high school home ec when I put a needle through my finger! It isn't always the little ones! I didn't have any home experience since my mom sewed but didn't teach. Start them out on a good machine and supervise. They will quickly learn how to the right way. Kids are so smart! I bought a kids machine for my 8 yr old granddaughter and it was so much a pain because it wouldn't stay threaded. Big mistake!

Start her out on a small machine like a featherwight. A lot of the companys have them now.

This machine is bought by a lot of quilters to take to retreats:
http://www.overstock.com/Crafts-Sewi...7/product.html

There is a nearly identical Janome marketed to adults (minus the Hello Kitty theme) and it's got a great reputation for ease of use and reliability.

I have never heard of any toy machine that functions well enough to teach a youngster to sew. They are so frustrating to operate that they could turn a child off of sewing forever.

The one exception is a Singer antique toy chain-stitching machine which is collectible and funtional, but I can't remember which one it was - the model 24, maybe?