Spice is a new herbal blend being sold legally in some locations and not in others. The ingredients according to users are herbal and natural. But when synthetic cannabis blends first went on sale in the early 2000s it was thought that they achieved an effect through a mixture of legal herbs. A Laboratory analysis in 2008 showed this was not true and that they in fact contained synthetic cannabinoids which act on the body in a similar way to cannabinoids naturally found in cannabis, such as THC. 
A large and complex variety of synthetic cannabinoids, most often cannabicyclohexanol, JWH-018, JWH-073, or HU-210, are used in an attempt to avoid the laws which make cannabis illegal, making synthetic cannabis a designer drug. It has been sold under various brand names, online, in head shops and at some gas stations.
Spice is smoked the same way organic cannabis is smoked. But unlike cannabis, it takes longer for the hit to take effect, but once it does, it's effects last much longer. For the novice user who may have experienced organic cannabis their belief that the drug will kick in normally might pose a risk to attempts to smoke much greater amounts than they would with the organic cannabis.
Parents need to pay attention to what their children are doing and using and yes your children can say to you "No, Mom this isn't illegal!" The difficult battle for parents, law enforcement and legislators is to stay aware of and involved in drug trends as they occur. As with these synthetic cannaboinoids, the legal system is slow to react and needs to be coaxed by legislators, parents and law enforcement. Regardless of legality, parents, adults, educators, law enforcement and legislators need to be proactive and involved in understanding several issues. First, anything that a teen uses to create an intoxicating or hallucinating state should be a concern. There are many legal products that teens and adults use that create a brief intense "high!" Products that are readily available and legal might include glue, dust off spray, paint, paint thinner and other household products. Second, because these products skirt the legal system and were never truly intended to be used to get a "high." the risk of side effects are greatly increased. The potential for side effects including exposure to cancer causing materials and psychological issues can be greatly increased. Lastly, you should have the conversation with your child or teen regarding their use and abuse of drugs. Parents who have those conversations greatly reduce the risk of your child experimenting or conducting risk taking behavior. This includes sending a clear unambiguous message to your child about your views of drug abuse and the risk surrounding it.
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