This simple lab covers types of reactions, balancing equations and moles. No wires necessary--just clear plastic cups, 9V batteries, and some thumbtacks. Use Epsom salt to make the electrolyte solution if your chemical supply is limited. Exact measurements not necessary, but I added about a spoonful of it for every 500 mL of water.
Scaffolded questions help the students describe what they are seeing and explain it with science!