Not cheap but my kids in that age bracket sew on a Janome Gem Silver. I use it as my back up travel machine and they learn to sew on it. Also I have some kids that sew on an older Singer 1970-s that some one gave me. You can pick those up for about $35. They work better then the cheaper newer ones in my opinion. I secdond the antique hand cranks eventhough that is not the one my kids use. Ofcourse they run more expensive and do straight stich only. Another nice machine that is straight stich only is the Singer 301. My personal favorite.