I've done 50 or so hickory board bows for kids. Kinda got a reputation for 'em at one time. 52" with a 4 inch handle and 1 1/2" fades will give enough limb for up to a 23" arrow draw. I came by the 23" draw by buying 48" dowels, cutting in half, allowing for taper and nocks.
Don't ask me about red oak bows, I'm on the losing side of 4 for 5 with the 5th one not having started tillering yet!