Not every activity is a large one. Sometimes we do small, simple things. We have a contingent of LEGO bricks that we send to schools and children gardens who ask us to do so. We call it "1 brick 1 smile". Sometimes, if team leaders or volunteers from club have time, they go and make a small presentation on some topic (it usually depends on age of children, safety on road crossing, pat and animal care, opposite from same age kids kindnes opposite to violence, future job deciding, robotics etc.
These are such two ocassions, kindergarden: "Tesla, science for life" and elementary "Laza Kostic" (more pictures here (link)