As I explained in my blog entry "Teaching Science Without Any Scientific Equipment" how science can be taught without any costly equipment, spending a lot of money on equipment is completely unnecessary for high-quality learning. (A good teacher is more important than any learning equipment could ever be.) That applies to other subjects too, not just science. The cheapest odds and ends, used properly, are just as effective for teaching as anything you could purchase at any price.
One of the most valuable pieces of educational equipment I have ever found is the simple index card or flashcard. I have had great success using that, especially for phonics and math.
For phonics, what I have done is write letter combinations, vowels or consonants, on the cards. For math, I would write times table problems (2x3, 4x5, etc.).
I like to make a game out of it. If I'd be tutoring more than one student at once, I would hold up the card. And whoever could answer it first (the product of the math problem or the sound the letters make) would get the card. If it would be just one student, then I would wait a few seconds if he didn't give the answer and I would get the card; otherwise he'd get it.
Speed would be especially important for the times table cards, because I want them to memorize the multiplication facts, and not have to figure out the answer. That is what builds proficiency in math. So that would have to be answered immediately; I would wait no more than a second or two before saying the answer and claiming the card.
Whoever ends up with the most cards at the end, is the winner!
The rules would sometimes have to be adjusted based on the individual student. You have to watch out that he doesn't get so frustrated and discouraged that he quits trying. It must be kept at just the right level, so that it is exciting and challenging, and neither so easy nor so hard that it stops working. As long as the student finds it hard but still wants to do it, then you know it's at just the right level.
You could use this for other subjects too. For geography, you could put little maps of states or countries on them, and then they would have to name it or give some piece of information about it. For grammar, you might put words on them and ask what part of speech that word would be. For learning a different language, it could have the word in that language to be translated into English or an English word to be translated into that language. Another thing I’ve done a lot with index cards is showing other alphabets: I’d find words in a language with another alphabet, such as Russian or Hebrew or Arabic or Japanese (katakana), which are almost the same as the word in English, and then, after explaining the alphabet, have kids try to sound out the letters or syllables and guess the words. I've also done this with Egyptian Hieroglyphics when teaching history, to let them see if they can guess from the pictures in the words what the words might be!
I don't even see any point in buying pre-made flashcards, when it's so simple to make them yourself. Sometimes I don't even buy index cards: I just use a word processor or graphics program to arrange the things for 6 or 8 flashcards on a sheet of paper, get some thick, heavy paper or card, run it through the computer printer, and then cut it up into flashcard-size pieces.