Get your class up on their feet and moving around to GoNoodle - a free resource (although paid-for content is also available) that focuses on mindfulness and movement activities to brighten your day! (I made the last bit up but it's probably going to help in that direction...)
Champs are the main motivation tool in GoNoodle - every time you complete an activity you help to grow your 'Champ' - there are at least 25 to choose from, available when you play more and more activities:
Have a look through a range of categories to suit the mood - be it a short 'brain-break' or something to calm down your tricky class after a boisterous lunchtime. Or something to break the transition between wet lunch and maths after lunch perhaps?
There are loads of cool channels to surf through, with specific styles of activity group together - 'Brainercise' with coordinated exercises to make you think as you move (at least I would have to think carefully...) to 'Zumba Kids' to 'Think About It'- that one setting a positive tone at the start of the day (and before you realise it's going to be a wet lunch...)