Well, I can help you out if you want to come to Italy!!! But I don't have a school.
I wish there were schools for this, because they try to sell stuff like muffins (taste like cupcakes, too sweet, one i had was full of candied fruit!!!) and brownies (dry and with practically no chocolate). Obviously they don;t know how and I wish they did. So i have to bake my own.
But american sweets are not difficult and if you have a good cookbook you can really reproduce them easily - I recommend the standard ones first, for a home cook. I learned cakes on the old 1950 version of the betty crocker cookbook. (Don't go near the new ones, they';re not good, but i did get my daughter a reproduction of the original at amazon). The cakes are foolproof. Brownies, muffins, pies, they're all good and mainly the recipes are well-explained and work very well. (The later editions use too many packaged ingredients.) I've tried many other standard cookbooks, like joy of cooking and fannie farmer, but they give less consistently good results - the betty crocker cookbook recipes always came out perfectly for me. Once you have the basic recipes, you can then go looking around for more.
For bagels and other stuff you'll have to go further afield. There are some other cookbooks that are also really good. (Unfortunately, many of the fancier cookbooks are influenced by european cooking, and that's not what you're looking for.
Rose Beranbaum has a cake book (The Cake Bible) that's really good - the best fudge cake I ever made is in there, and others, too. I found some really good muffins in the cooks illustrated magazines and cookbook (Baking Illustrated) though i find they aren't always to my taste. (Always add more salt than they say! their stuff always is short on salt.) Bagels are not really hard, they just take a lot of time and a lot of work since they have to be kneaded, allowed to raise, shaped into bagels, raised again then boiled then baked. Totally worth it, but you end up eating a whole batch in one sitting because they're so good! Probably not advisable. But you might freeze them, for instance, slicing them first.
In the case of using these books in europe, if Italy is any indication, the flour is very different - our flour here in europe is "weaker" as compared to american flour which is "stronger" - that is, american flour is more suited to bread baking, has more gluten and so requires and takes more butter than european flour. So if you make chocolate chip cookies, and pie crusts, in particular, you will have a greasy mess if you just use the recipe as is. And cakes will be more dense and low-rising. You need to significantly increase the flour and reduce the butter (european butter has less water, so it's greasier). I'd say a tbsp more flour per cup for an american recipe. A tbsp less butter per cup. I can help you work out the weight equivalents, since each ingredient weighs differently so going from cups to grams is complicated - more grams for butter and sugar, less for flour and cocoa. Once i figured out the butter/flour business, i could bake everything from american cookbooks here.
So I don;t think you need a course (even if it would be fun). I learned everything from cookbooks. And another thing the old betty crocker cookbook had is good illustrations of basic techniques, which since they're different from european baking techniques sometimes, can be very useful. Also that book was for a kitchen that was more like a european kitchen, with fewer gadgets, and fewer convenience foods. It shows how to do some techniques by hand that modern ones only show with mixers.