Remeber the Mora does not have a micro bevel on it , or should not. The bevel is the a saber bevel i.e. the whole sloped part of the blade is the bevel. You should sharpen the blade at this angle though with a file it might be harder. Maybe a small sharpening stone would be good to carry.
For wittleing you might get some of the more special purpose wittleing knives mad with a shorter blade. But it sounds like you are having fun and the kids are leaning valuable skills.
cheers