With older students in mind including those about to enter higher education, there are many free resources available to support students in their study of Mathematics. Note that a new blog aimed at students is now available.
There are many sources of excellent notes online, a page on Mathematics for Students – Notes has an excellent collection.
I would advise students of any subject to learn to use WolframAlpha. Suppose you wish to do some revision on techniques for differentiation for example – ask WolframAlpha to differentiate x2sinx, and the derivative will be returned with possible working available if ‘Show steps’ is selected. (Further Calculus examples). WolframAlpha provides an excellent way to check your work.
A variation on crosswords are crossnums where the clues are all sums, see for example a good selection ofCrossums from Teacher Resources on Line(a site developed by the late Frank Tapson, who worked with CIMT which is well worth exploring). This collection includes a blank template so students can create their own puzzles.
Make your own crosswords with excellent free software – Eclipse. The grid shown in the image above was generated by the Eclipse program. Click on the image to download the crossword and solutions as a pdf. The program is very straightforward to use and includes a clear tutorial section. See the Reference page for inspiration for crossword clues. Transum created this interactive crossword with the software from Eclipse. (The crossword is in fact one of the resources on the excellent ‘Starter of the Day‘ site.)
WolframAlpha can be used for vocabulary, for example, try typing ‘plus’ into WolframAlpha.
Note that WolframAlpha has assumed plus is a character but you can choose to refer to a mathematical definition or a word (or an internet architecture topic). Choosing wordwill not only give definitions but a wealth of other information that you would not find in a dictionary such as the first known use of the word, frequency of use, rhyming words and much more!