Boys Scouts used to teach making their own non-toxic firestarters and canned heat.

For the firebugs, take 2-4 sheets of newspaper folded normally (along the spine). Roll up tightly -- should be approximately the thickness of 1-2 thumbs. Tie closed 1" in and at 2" intervals with cotton twine -- I use square knots. Leave a good 2-3" piece of twine dangling from the knot. Cut midway between the twine so you have approximately 2" segments tied shut in the middle. Hold by the "fuse" (that 2-3" piece you left hanging from the knot) and dip into melted paraffin wax. Let wax soak into newspaper -- I forget how long this takes but it's not long. Drip drain and then dry/cool/harden on a clean piece of newspaper or waxed paper.

For the canned heat, take a clean dry tuna fish can (or similar size can). Cut corrugated cardboard in strips as wide as the can is tall so you can lay them inside the can and see the corrugation from the top. The strips should sit just under the lip of the can. Fill the can with the strips, preferably laying them down in a spiral coil for best density without packing the can. Pour melted paraffin wax into the can until it just hits the top of the corrugated cardboard (don't go over the top of the cardboard or it will drown the flame when it melts).

Both of these are very portable, light, easy to make and non-toxic. You may want to throw them in a plastic bag during very hot weather.