When reading a text, give them reading rules to spice things up. The sillier the better. E.g. Everytime you read a word with the letter a in, you have to read it twice. Everytime you have a word with an e, you have to stand up and sit down. If you have a word with an a and an e, you have to read it twice and of course stand up twice. You can also do it using rules for semantic fields, verb tenses, etc. You can make your own rules and combine multiple rules to increase the difficulty level for them, depending on age and skill level. Most of my 13 year olds start freaking out after 4 rules, but they know this game, most novices will start going wrong after 3.