Oh yeah the kids one is fine. I bought an “official” mat just like it because it had lines drawn in it that I thought would be helpful.
They’re not at all. It’s hard to properly line anything up against them. Instead I use one of these:
It’s awesome, I hook the top part on the top of the foam piece and line my project against the ruler part. I pin all down that, pulling the project to the ruler the whole way down. It makes a perfect straight line. Then I rotate the piece and do another side. In the end it makes a perfectly square piece.
I bought one of those rulers for myself just for blocking. I love to block I think it’s so satisfying pulling and pinning a square perfectly straight.
Bigger projects are done in piecemeal by putting more puzzle pieces together to fit the size.
it looks like this https://www.amazon.com/IRWIN-Combination-Square-Metal-Body-1794469/dp/B005XUHIBG/ref=sr_1_1?ie=UTF8&qid=1481037968&sr=8-1&keywords=compound+square
but I think it was my grandfathers prob 30+ years old so I assume its good. I can look into getting a digital one though.
Combination square. They're missing the ruler part: https://www.amazon.com/Tools-Combination-Square-Metal-Body-1794469/dp/B005XUHIBG/
This is what I have been using and it is great - perfect 90 degree corners and straight lines
https://www.amazon.com/dp/B005XUHIBG/ref=cm_sw_r_cp_api_Q0YfzbMQW2PYX
I measured/marked the holes using a combination square. Then I drilled 5/8 holes in opposite corners cut area. Then I used a cheap ($20) electric jig saw to cut out the area as best as possible. I would follow the lines on one side, then flip it over and cut it again. The jig saw blade bends so it cuts on an angle. Finally, I used a chisel to remove excess material and clean up the holes and straighten them out.
Combination Square https://www.amazon.com/gp/product/B005XUHIBG/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1
1" Chisel (or you can get a set of three for a little more) https://www.amazon.com/IRWIN-M444-1-Inch-MARPLES-Chisel/dp/B0000CBJH8/ref=sr_1_20?ie=UTF8&qid=1493124918&sr=8-20&keywords=irwin+chisel+marples
Mallet https://www.amazon.com/gp/product/B00020JNDI/ref=oh_aui_detailpage_o09_s00?ie=UTF8&psc=1
What are you going to use the #4 plane for? Planing without a solid workbench and vise/hold downs is a chore. Perhaps a block plane or even sandpaper would be enough to get you started?
Square - get the Irwin combo, it's accurate enough for casual use. https://www.amazon.com/IRWIN-Combination-Square-Metal-Body-1794469/dp/B005XUHIBG
That stone is too coarse for woodworking tools. Either use sandpaper like others have suggested, or get the King 1000/6000 https://www.amazon.com/King-Sided-Sharpening-Stone-Base/dp/B001DT1X9O
I would argue that the chisels, while crappy, will make good sharpening practice. Or get the $5 Harbor Freight ones and sharpen them every 5 minutes - at least you'll become a sharpening expert fast.
A functional combo square doesn't have to be a Starrett, at least not for woodworking.
That's like looking at this and saying that marking gauges are too expensive.
I've been using this square for years and it's great.
Learning how to cut basic joinery a good start. Lots of people start by learning how to cut dovetails by hand. If you can make those nice and clean, you're just 4 joints away from making the main portion of a box.
For a small-time hobby level of woodworking, you'll need a few things (I included some links of some inexpensive recommendations that would be suitable for a beginner, but not so crappy that they'd frustrate you):
Combination Square - I have one of these, and you can't beat it for the price.
Chisels - you can get by with a super cheap set from a big box store or Harbor Freight, but they won't hold an edge quite as well as the linked set.
Saw - you can pick up a similar saw at Lowe's for $15-20. This handles both rip and crosscuts (along the grain/across the grain)
Marking gauge - you can get by with a pencil, but it's not quite as accurate
Bevel gauge - to mark angles consistently. The link is mainly so you know what they look like. You can get one for $5 at Lowe's or HD.
Mallet - Basically a hammer with a non-marring striking surface so you don't ruin your chisels
When it comes to making actual projects, you'll need some additional tools--check out /r/woodworking if you feel like getting into it--they have some basic tool lists for beginners, depending on what you'd like to accomplish.
Aside from joinery practice, many beginners make a workbench as their first project. That's fairly involved, but there are tons of resources available, and making your own bench can be inexpensive (I make furniture to sell as a side gig, and my bench is made from 2x4s from Lowe's) and will teach you a whole hell of a lot.
Here are some videos to check out that explain some basic techniques and principles:
Cutting dovetails: https://www.youtube.com/watch?v=-3w20JGFPek
Dimensioning boards (this is for when you start with rough-sawn lumber): https://www.youtube.com/watch?v=m231_HKCOWs
Sharpening is the other aspect to all this that you'll need to learn and practice. The cheapest short-term uses sandpaper and a pane of glass--check out the Scary Sharp method. It's not cheaper than buying nice stones in the long-term, but you don't have to drop $100+ on diamond plates if you're just getting a feel for the hobby.
If you have any questions, feel free to shoot me a msg.