Homework help: Back to school means that  more resources might be needed by students and by harried parents trying to answer the questions of their student offspring.  You can find all you want (and probably more than you’ll ever need) on almost any academic subject at an Internet site called ABCentral.  The site is designed for teachers and grows by expert selection of web sites suggested by subscribers.  For most purposes you will want to use the EDUMAP section of this site.   Caution:  It's possible to get caught in a loop:  there is a link at the bottom of each EDUMAP page marked "return to the ABCentral", and that's the only way to return to the original ABCentral page to look up another subject on the EDUMAP.   The internet address for ABCentral is http://www.my-edu2.com/index.html