Emusictheory.com helps students learn note names and notes on the fingerboard. The student reads a note and must press the correct location of that note on a virtual string—for any string instrument. It also has drills for teaching rhythm and key signatures. Great stuff!!!
www.musictheory.net has both training sessions and drills. The drills help students practice and improve what they already know; they can be modified to match the student's instrument and ability level. The training programs help students learn how to read music better by explaining the rules behind musical notation. The range of lessons is very wide, starting with beginning material and going all the way up to college level theory. This is also a drawback because it can be overwhelming. Students should stick with the easier lessons, unless they are in AP Theory.
www.drumbot.com is a simple guitar tuner that helps you tune your instrument by ear. This site also includes a set of drum loops that you can queue up and save (for "those who can't find a real drummer to jam with"), a metronome, a drum pattern sequencer to create your own drum loops, and tap BPM, an app that tells you how many beats permit you're hitting your keyboard at. You can even download all the apps to your computer, if you prefer to access them locally.
Practice Sight Reading rhythms of all meters and difficulty levels at this website.
Rhythm Reading Website for basic rhythmic reading