This is a unit I put together using both CA's old Social Science standards and the new C3 Framework and Inquiry Design Model, based on "Agriculture in the Past and Today." It was designed with 2nd Grade in mind, but I believe it could easily be leveled up or down!
IDM Unit Plan
Pictures for Agriculture Stations
Observations Graphic Organizer
Pros and Cons Organizer with Glossary
The first part of the unit includes a lesson in which students explore stations with 'artifacts' of agriculture from different places and time periods (Ancient Mesopotamia, Ancient Greece & Rome, the 1830s, and the 2000s). It could also be expanded to include other time periods and places, but for the sake of time I kept it at four stations. Included are pictures, book and passage recommendations, a teaching guide, and an observations worksheet.
The second part of of the unit includes a timeline lesson in which students may paste their observations into a general timeline of events (really old vs. more recent). This also includes a general teaching guide and a timeline worksheet.
Lastly, there is a section on modern agriculture's pros and cons. It can be expanded with videos and direct instruction, but I kept it simple with reading a passage from the CA Wonders book and the pros and cons worksheet that is included! I think this provides a more balanced approach than the typical "modern farming and technology is good..small family farms....etc."
D2.His.2.k-2 (C3): compare life in the past to life today
D2.His.9.k-2 (C3): identify different kinds of historical sources
CA SS Standards
HSS 2.4.1: describe food production and consumption long ago and today (including roles of farmers, processors, distributors, weather, and water/land resources)