[klperry]

Use poker chips as counters, maybe the reds could be - and the blue or white +. Buy them from a dollar store and actually write the symbols on them. Start small with numbers less than 10. After they can master those, build up to numbers less than 20. Let them work in pairs so they can share chips. After students can do problems with numbers up to 20, ask them if they can discover patterns or rules. Also, you could have them draw the - and + "chips" and cross out.

Example: -5 + -3=?

Draw: - - - - - and - - -= -8

or -9 + 5=

Draw: - - - - - - - - - and + + + + +

teach them it's like a balance scale: cross out 5 - and 5 +...
Whatever is left is the "balance"


I also use word problems like "How owe me $6, you go shopping and borrow $6 more to spend, how much do you owe?" "If you owe is it positive or negative?"

Hope this helps!