Word Joust K-5:

This version is specifically designed for elementary school students (K-5th grade) with grade-appropriate words. With Word Joust for K-5, knaves (i.e., you) will master the 300 most popular words using in elementary school reading materials. Delivered as mini word games set on a medieval battle field, Word Joust makes learning new words easy and fun. This app includes five active games that involve spelling and memory involving the vocabulary. You can also track the progress of the students and how they are moving through with their words. This app is free and is available on iOS 4.0 and later.

https://itunes.apple.com/us/app/word-joust-for-k-5/id461456879?mt=8