This series of Word Wheels books will keep you challenged and entertained for hours.
How it works
Study the letters on the outside of the wheel and note the one in the middle. Try to create as many word of 4-letters or more using the letters on the available letters only once. Every word must include the letter in the center of the wheel.
At the back of the book as every possible anagram solution for each combination of letters, so you can check your anagram creating skills.