Molecular Model kit – The bookstore carries a Maruzen model kit for $28 that I highly recommended. A model kit is especially useful in Chem 21 for helping you understand topics in Chap 4 (Newman projections and Chair Conformers) and Chap 5 (Stereochemistry).
o Maruzen HGS model Kit 1003Alpha Organic Chemistry Basic Set includes 28 carbon atoms and orbital plates
Here are some additional options from Maruzen to consider:
Budget option #1 for $16: Maruzen HGS model kit (1000Alpha/Fundamental Organic Chemistry Set) includes 12 carbons and 6 oxygens and lots of hydrogens; can build basic things, but downside is does not have orbital plates
Budget option #2 for $17 1013Alpha/Organic Chemistry Set for Student. This set includes orbital plates that help you to see p orbitals and pi bonds, but at the trade-off of giving you less atoms. This set includes 9 carbons, 4 oxygens and lots of hydrogens (which is less than the option above). But this is still enough to build one model at a time of any organic molecule you are interested in.
Pricier option for $50: 1005Alpha/Organic Chemistry Standard Set Includes orbital plates and has an abundance of atoms (38 carbons and 8 oxygens and lots of hydrogens) so you can build multiple models simultaneously (without having to always dissemble the previous model you built)