Free Handwriting Resources
I've spent most of my life hearing that "nobody will need to learn handwriting soon, because everything will be typed," but I don't see that happening at all. From thank you notes to quick notes left on the fridge for my husband, I end up writing something every day. There's also research that shows that we remember something better if we've written it down by hand. I'm a big supporter of teaching cursive before manuscript handwriting, as is common in some parts of the world: we can quibble eon that, but not on whether handwriting is important.
Free Copywork Resources
I'm a big fan on practicing handwriting via copywork: carefully copying a sentence (or, as students get older, a group of sentences). Slow and steady is the name of the game, so passages should be short, even for older students. As students improve their muscle memory, their everyday handwriting improves, too. It's also a great way to practice spelling, and as students get older can be a way to spend some time with famous quotes, poetry, or anything else for which a little goes a long way.
This is a 1916 book designed to teach spelling via copywork, but it's also just a really nice, simple collection of sentences that you can use for your child to copy. I used this book with my oldest for a while. I'd copy out a lesson in my nicest handwriting, and I'd have her copy it. There's a Book 2, too.
Free Handwriting Worksheets
When I was a teacher, I used this worksheet generator literally every day, to make homework for students to copy and make games with their spelling homework. It's also a great little handwriting worksheet generator, that offers both manuscript and cursive options.