Back 2 Back
Challenge the kids to stand straight up from a sitting position without using their hands.
Some will do it, others won't.
Then get the kids to sit back to back....Ask them to stand up leaning on each others backs.
Use this as a simple starting activity to talk about how sometimes we need help.
As you get older this gets tougher and tougher, so even if they could do it on their own one day they'll need someone's help!