Introduction: Which brand of sunscreen will protect you the most? Sunscreen is a substance that provides a high degree of protection against sunburn, often preventing most tanning and sunburn, as it blocks the penetration of ultraviolet rays. Sunscreen is almost a necessity for most people. Sunscreen is almost a necessity because some people burn easily due to sensitive skin. This could be very painful for some people and does not go away easily or quickly. Two types of radiation that cause skin cancer are ultraviolet A and ultraviolet B. These two UV rays can cause sunburn, skin aging, skin damage, and skin cancer. That's what sunscreen is for. It protects the skin from these rays which can permanently damage our body. We decided to carry on this project because we all like being outdoors, having fun and doing sports. We believe sunscreen is necessary because we don't like getting sunburned. Also because as we get older we don't want our skin to get old, damaged or get skin cancer. One thing we'll talk about is why UV rays affect us. Another thing is how long it realistically takes for sunscreen to stop working. The last thing is what's in sunscreen that really helps us. This experiment will show which brand will keep us more protected and safe from the earth's UV rays which are so harmful. Body: There are many different reasons to wear sunscreen. A couple of reasons are that without it you can develop sunburn, skin damage, aged skin, and/or skin cancer. These are common among careless, repetitive tanners and among people who refuse to wear sunscreen when they know they will be outdoors for an extended period of time. It is never good not to wear sunscreen when going outdoors....... middle of paper...... because they are the two things that affect our body and skin when exposed to the sun . Knowing what SPF and how long your body can tolerate the sun is also very important because using too low an SPF could leave negative effects on our body and therefore it could be exposed to the sun for too long. Knowing which ingredients in sunscreen protect us is a good thing to know because when you buy sunscreen you will want to look for those ingredients. It's also important to know what the best physical sunscreen is. This is because you would want to find it on top of chemical sunscreen. In our experiment, we will test to see which brand of sunscreen with SPF 50 will protect one sun strip over another sun strip. Works Cited • www.coppertone.com • www.bananaboat.com • www.nivea.com • www.dictionary.com • www.skincancer.org • www.aad.org • http://health.howstuffworks.com