My kids needed some mittens and I figured I could make them some from some fleece scraps I had "lying around." I found another tutorial online for fleece mittens and I really liked them. But I looked at a pair of store bought fleece mittens that I had and I liked the way they were constructed a little better so I altered their pattern to work the way the store bought mittens did and I really like the results.
You don't have to use this pattern, but it will give you an idea of what it's supposed to look like. I actually made patterns for my 3 older ones by tracing their hands, drawing an upside-down U about 1/2" all the way around their hand (fingers together, not spread out), marked where their wrist was (for the elastic placing), and finished the pattern using this as a guide.
The original tutorial said to enlarge the patterns till the grid was 1 inch square (for adult size), maybe 3/4 inch square for a child's hand. Play around with the sizing, find what works for you.
I trace the hand 1/2 inch in from the fold (on a piece of paper folded lenghtwise), make the upside-down U, fold it in half again and cut the rounded part off the top (to make sure it's nice and even on both sides). Then I fold the thumb side in half to the middle fold to get the thumb width. Fold the paper in half from top to bottom to find out how far the cutting line for the thumb should go. Then about 1/2-way from the top of the thumb cutting line to the bottom of the mittens, start drawing the curve for the thumb-tip. Fold the paper in half again from edge to thumb cutting line and cut the curve for the rounded thumb-tip. Fold the thumb part up and make the pattern piece for the thumb. Make it a little longer than it calls for, then cut down if need be. I discovered that the thumb pattern piece runs a bit short.
To cut out the pieces, fold over a piece of fleece, line the pattern up on the fold, and cut the rest out. Then open the fleece, lay the opened pattern on top of it and cut out the thumb flap. If there is a right side and a wrong side to the fleece, make sure to flip the pattern over when cutting out the other thumb flap.
To sew, line up the thumb pattern piece with the thumb flap, sew from the notch around to the other side of the thumb. Stop. Line up the long edge of the thumb piece with the long part of the main mitten piece, and sew together. Sew some elastic to the wrong side where the pattern indicates (or where you noted the location of the wrist). Place right sides of mitten together and sew mitten together. Hem the edge. Turn inside out, enjoy :)