Website Review: howmanysyllables.com
In short: Rules for how to count syllables. Knowing how many syllable are in a word is important for lots of things. For example, when students are learning how to make comparisons, they need to know how many syllables an adjective has before they can make it into a comparative.
For students: Type any word into the homepage to learn how many syllables it has quickly.
For teachers: Not every student needs this, so just be ready with the information (or a link) when it comes up.