I like the Kuretake No. 8 with Platinum Carbon Black ink cartridges. It's a good economical option.
The brush is soft, but springy. The Carbon ink dries quickly and is quite waterproof for use with washes.

I use Illustrator and create palette boxes outside my artboards, typically I only need to find one or two colors, then I'll use the color guide and harmony rules to generate complementary/high contrast colors according to them. Works really well.
Also material design palette Made for UI design, it's a pretty cool color application of Google's Material Design standards.

I have a "Flip-Pal" scanner. It's only 4x6, but its made to scan large items -- I use it to scan 11x17, and even posters up to 36x48 (of course, there is no limit to the size)

The idea is that you scan the object/paper in multiple pieces, then stitch them back together with included software (or more preferably photoshop)

This has been the cheapest and best solution. Not to mention it's completely portable/battery powered, so you can bring it with you easily.

Make your own contract or modify one. Things to include:
Ownership of works(you own it until paid for in full).
Pay schedule (money down, pay milestones and final payment due usually I make this payment in full before finals are delivered).
Dissolution of contract( a way out for client and you if things go south who is going to pay what for percentage of work complete).
Scope of work and project creep(what you will do and set number of revisions; and what will happen if things change.)
There are boilerplate contracts out there for just about everything; that you can modify for your needs.

Find printable templates, print them and trace them on cardboard to use it as a stencil for the kids. Cut out and let them decorate it. Also, I really like pinterest for kid stuff. I've done a lot from there already. On pinterest search for 'quick science experiments' and you'll come up with a boat load of stuff. We've made sidewalk chalk, crayons, tons of stuff.