Tips for Adults

Use text prediction software to write emails and other communication. Most word processing software has spell-check and grammar-check features. Take full advantage of what they offer.
In meetings, ask for verbal brainstorming sessions and for the note-taker to type up their notes. Or if you are assigned to be the note-taker, take notes on a laptop with a projector instead of hand-written on a whiteboard.
Work with a colleague to put together an outline first to make sure you can keep track of the content of a longer writing assignment
Ask for task instructions in verbal format. If your supervisor can talk through instructions by phone or voice memo, it may be easier for you to get started.
After you compose something, walk away or work on a separate task and come back to proofread it with fresh eyes. (This helps everyone!)
Don't be hesistant to ask a friend or colleague to proofread for you. Many people will be happy to do it.
Just pick up the phone. Although many offices have an email culture, it may save you a lot of time and effort to clarify something by phone instead of back and forth emails.