This is an awesome website that takes different math topics, vocabulary, etc., and makes mnemonics to help students remember what the topic or vocabulary words is. The website also contains really great lesson ideas and professional development articles to better stay in the know.
AAAmath is very user friendly as it is sorted by grade level and subject. Here is what AAA math says about their website: "AAA Math features a comprehensive set of interactive arithmetic lessons. Unlimited practice is available on each topic which allows thorough mastery of the concepts. A wide range of lessons (Kindergarten through Eighth grade level) enables learning or review to occur at each individual's current level. Immediate feedback prevents practicing and learning incorrect methods, which is a common result of traditional homework and worksheets. Practice can continue as long as desired in a non-threatening format which helps build self-esteem and confidence."
This website provides teachers with many lesson plan ideas that integrate different subjects into math topics. While they are set for high school students, there are some that could be easily fixed to fix middle school students too.