Work in progress!!
Other resources and inspirations:
(you can also follow the link from his blog).
How many ancestors I had 900 years ago?
Subject: Multiplication, powers, and exponential growth.
Pre-req: Multiplication, powers.
Email me for password (from your teacher email): zachi at baharav dot org
Questions/Comments: Zbaharav at Kehillah dot Org or Zachi at Baharav dot Org .