Well done for making the effort to get some seriously good food into your family's diet.
Swapping out the wheat...
Acorn nut and flour
I have tried this myself, although I do not use acorn flour on a regular basis, it is great to do on the odd occasion when you have plenty of time, soak acorns in fresh water, preferably for 24 hours, change water every few hours, (obviously not needed overnight as you would be sleeping!). When water is clear then you are done. This leaches out all the tannin which can otherwise be harmful and very bitter tasting. Once acorns are leached, then dry them off, and roast them in a low oven. This may take an hour or two, do not let them go black. Once cooked then shell them. You can shell them before cooking, but I find it is easier to get the shells off afterwards. Put the shells in compost bin, then use the central part of the acorn. Grind it up, blender or pestle and mortar are both fine, or use whatever method you find easiest. Even wrapping them in a tea-towel and bashing them with a rolling pin works haha. The desired consistency for your finished product is small nutty chunks, if you want to use them to flavor food, in place of other nuts. They can also be used in place of peanuts for
acorn butter. The desired consistency if you want to use them as flour is more milled, so use the pestle and mortar on the chunky bits, and grind them right down. Then use as you would normally use wheat flour. Personally when I am making bread with acorns, I tend to use wheat flour and acorn flour half and half, and toss in the smaller chunks of acorns, aswell as the more ground down floury stuff, this makes a lovely nutty loaf. But if you want 100% perennial crops, or have allergy to wheat products, then 100% acorn flour is great to use, as long as you have done the leaching process to remove the tannin.
One oak tree can give a huge harvest every year, literally thousands of pounds from a mature oak, if you can beat the squirrels to them. But if you are going to plant your own oak, then remember 2 things...
1. Obviously they do grow very slowly, but can live for hundreds of years, and you will not get much of a crop for at least 5 years, 10 years before you have an actual tree sized oak.
2. Oaks come up as male and female trees. So if you are planting oaks, it is a good idea to plant more than one, and also not all females produce a lot of acorns. Traditionally many oaks were planted, and then the best croppers and a couple of the largest males were left to grow, the rest thinned out for timber. However they do not need to be planted very close together to pollinate each other, an oak at one end of a football field can easily pollinate an oak at the opposite end of the field.
Having brought up 4 children, I can also say that no matter what you put on the table, at least one of them will make some fuss about it, but remain firm, remember you are helping them to be more healthy, which is a very important task, and don't just throw out every recipe that they turn their nose up to, try it a few times and they will get used to it, and grow to love it