Electronics, Robotics, ROVs, etc.

Where to get stuff:

Parts Finder

http://www.octoparts.com/

Components, kits, etc.

http://www.kr4.us/
http://www.mpja.com/
http://www.adafruit.com/
http://www.sparkfun.com/
https://solarbotics.com/
http://www.seeedstudio.com/
http://www.makershed.com/
http://www.digikey.com/
http://www.mouser.com/
http://www.jameco.com/
http://www.taydaelectronics.com
http://www.allelectronics.com/
http://www.elexp.com/
http://www.newark.com/ 
https://www.mcmelectronics.com/
http://www.goldmine-elec-products.com/
http://www.jdr.com/
http://www.alliedelec.com/

Tools, Materials, etc.

http://www.micromark.com/

www.mcmaster.com

Cheap Chinese Stuff

https://www.fasttech.com
http://aliexpress.com
http://www.alibaba.com/ 
http://www.lightinthebox.com/

Hobby

http://towerhobbies.com/

For Teaching Kids

http://www.adafruit.com/blog/category/circuit-playground/

http://sylviashow.com/

http://makered.org/youngmakers/

General information

http://makezine.com/
http://www.instructables.com/id/Basic-Electronics/?ALLSTEPS

http://makezine.com/2016/01/16/how-to-use-a-multimeter-video-tutorial/

Circuit Board Design

http://fritzing.org/home/
123D Circuits http://www.autodesk.com/products/personal-design-and-creativity/apps
http://makezine.com/2015/07/14/design-circuits-web-based-circuit-simulator/

LEDs

LED series/parallel array wizard http://led.linear1.org/led.wiz
LED tutorial: https://learn.sparkfun.com/tutorials/light-emitting-diodes-leds
http://www.evilmadscientist.com/2012/resistors-for-leds/
http://www.evilmadscientist.com/2009/wallet-size-led-resistance-calculator/
Simple LED projects: http://www.evilmadscientist.com/2013/roundup-led/
Blinking LED with a 555 timer:
   http://www.instructables.com/id/How-to-make-a-fast-blinking-LED-bike-light/
   http://houseofjeff.com/555-timer-oscillator-frequency-calculator/
   http://www.ohmslawcalculator.com/555_astable.php
   http://www.doctronics.co.uk/555.htm

Transistors

http://www.talkingelectronics.com/projects/TheTransistorAmplifier/TheTransistorAmplifier-P1.html

USB with .NET

http://channel9.msdn.com/forums/TechOff/234037-Programming-Net-to-use-USB-device/
http://www.vsj.co.uk/articles/display.asp?id=600
http://www.icsharpcode.net/OpenSource/SharpUSBLib/default.aspx

Small Computers

http://www.kano.me/

Arduino, etc. 

Phidgets

http://www.phidgets.com/products.php?category=1
http://www.trossenrobotics.com/phidgets.aspx

TI LaunchPad

http://www.ti.com/ww/en/launchpad/launchpad.html?DCMP=mcu-launchpad&HQS=launchpad

Arduino

Online code editor for Arduino https://codebender.cc/
http://www.goldensection.cc/wp-content/uploads/Arduino-Quick-Reference.pdf
http://blog.makezine.com/archive/2011/02/why-the-arduino-won-and-why-its-here-to-stay.html

Control a motor with an H-Bridge http://itp.nyu.edu/physcomp/labs/motors-and-transistors/dc-motor-control-using-an-h-bridge/

Arduino Tutorials: http://www.jeremyblum.com/category/arduino-tutorials/

Programming ATtiny chips 

https://learn.sparkfun.com/tutorials/tiny-avr-programmer-hookup-guide/
http://highlowtech.org/?p=1695

Graphical Programming

https://learn.sparkfun.com/tutorials/alternative-arduino-interfaces
https://github.com/gasolin/BlocklyDuino
https://github.com/taweili/ardublock
http://www.modkit.com/

ROV

http://www.homebuiltrovs.com/
http://www.phidgets.com/phorum/viewtopic.php?f=13&t=2735

Development

Microsoft Robotics Studio http://www.microsoft.com/robotics/

Programming For Kids

Max/MSP - visual programming language. cycling74.com. Free variant PD puredata.info

3D Printing

Open source 3D printer: http://reprap.org/
http://www.yeggi.com/

http://portabee3dprinter.com/shop/portabee-go/
https://printm3d.com/themicro/
http://us.xyzprinting.com/ (da Vinci)

Creating a cheap 3-D printer, CNC machine, laser engraver
http://www.tinkernut.com/portfolio/how-to-and-how-not-to-make-a-cheap-laser-engraver/
https://www.youtube.com/playlist?list=PLlg8lN4r9qWiAOUi3TW3CUr0LOI3S0zpZ
http://www.instructables.com/id/20-CNC-Machine/

Projects

http://www.allaboutcircuits.com/
http://www.clubjameco.com/
Metal detector: http://www.555-timer-circuits.com/metal-detector.html
https://www.youtube.com/watch?v=afbEyvtPgm8
http://www.easytreasure.co.uk/bfo.htm

Thunder Tumbler Hack: http://www.instructables.com/id/Robot-Platform-including-h-bridges-from-10-RC-Ca/?ALLSTEPS

Brushbot
Crystal Radio
FM Radio http://makezine.com/projects/raspberry-pirate-radio/
Theramin
voice changer
beetlebot
Drawdio: http://store.cutedigi.com/drawdio-kit/
http://archive.makezine.com/pub/au/Charles_Platt

BEAM Robots
http://junkbots.solarbotics.com/sample_chapter/sample_chapter.htm
http://www.solarbotics.net/library/

Line following robot
http://playwithrobots.com/simple-line-follower-robot/
http://playwithrobots.com/dc-motor-driver-circuits/

Hovercraft
http://makezine.com/projects/3d-print-rc-hovercraft/

The Ultimate STEM Guide for Kids: 239 Cool Sites About Science, Technology, Engineering and Math

http://www.mastersindatascience.org/blog/the-ultimate-stem-guide-for-kids-239-cool-sites-about-science-technology-engineering-and-math/