Previous homeschool bloggers have given curriculum guides for the second grade according to subject. The purpose of this guide is to put all of the suggestions in one place allowing homeschoolers to build their own curriculum around the basics. You can use these suggestions which include website links and books your children should read to map out the second grade year for your homeschooler according to national standards.
For a simple no frills guide for second grade mathematics, read What Your Second Grader Should Know: Math by Valorie Delp. This guide covers second grade math basics such as counting to 1000, addition, subtraction, fractions, decimals, ratios, and more.
For second Grade Social Studies, What Your Second Grader Should Know in Social Studies includes lessons centering mostly around patriotism, community, and geography. (My personal recommendation is to teach your child history in order, and in the second grade, they would concentrate on the Medieval/ Renaissance time period.)
For language arts, What Your Second Grader Needs to Know: Language Arts recommends reading, dramatization, story development, listening skills, alphabetizing, vocabulary development.
A second grade reading list by Charisse Van Horne give 25 books your second grader should read as well as some links to sites that will get them to read.
Science in second grade would cover a lot of topics. These topics are outlined in What Your Second Grader Should Know: Science. They include animals, paleontology, ecology, botany, earth science, physics, and astronomy.
Other things a second grader should know are personal hygiene, food groups, diseases, and neighborhood safety.
What Your Second Grader Needs to Learn. This in the Education blog and written for parents of public school students.