I've made 100 flashcards of words with silent E and their non silent e counterparts (ex. there is a card for both slide and slid). There is a mix of nonsense words and real words. You can play Around the World with these or use them as flashcards.
You can also time your children to see how many they can do in a minute, and graph their scores.
To print, make sure it is in handout, 6 to a page form so you don't print 100 full sheets.