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Winter conditions are rapidly changing in temperate ecosystems, particularly for those that experience periods of snow and ice cover. Relatively little is known of winter ecology in these systems, due to a historical research focus on summer 'growing seasons'. We executed the first global quantitative synthesis on under-ice lake ecology, including 36 abiotic and biotic variables from 42 research groups and 101 lakes, examining seasonal differences and connections as well as how seasonal differences vary with geophysical factors. Plankton were more abundant under ice than expected; mean winter values were 43.2% of summer values for chlorophyll a, 15.8% of summer phytoplankton biovolume and 25.3% of summer zooplankton density. Dissolved nitrogen concentrations were typically higher during winter, and these differences were exaggerated in smaller lakes. Lake size also influenced winter-summer patterns for dissolved organic carbon (DOC), with higher winter DOC in smaller lakes. At coarse levels of taxonomic aggregation, phytoplankton and zooplankton community composition showed few systematic differences between seasons, although literature suggests that seasonal differences are frequently lake-specific, species-specific, or occur at the level of functional group. Within the subset of lakes that had longer time series, winter influenced the subsequent summer for some nutrient variables and zooplankton biomass. National Science Foundation (NSF DEB) [1431428, 1136637]; Washington State University; Russian Science Foundation [14-14-00400]; Ministry of education and science of Russia Gos-Zasanie project [1354-2014/51]; Natural Environment Research Council [NE/J00829X/1, 1230750, NE/G019622/1, NE/J010227/1] Funding was provided by the National Science Foundation (NSF DEB #1431428; NSF DEB #1136637) and Washington State University. M. Timofeyev and E. Silow were partially supported by Russian Science Foundation project No 14-14-00400 and Ministry of education and science of Russia Gos-Zasanie project No 1354-2014/51. We are grateful to Marianne Moore, Deniz Ozkundakci, Chris Polashenski and Paula Kankaala for discussions that greatly improved this work. We also gratefully acknowledge the following individuals for contributing to this project: John Anderson, Jill Baron, Rick Bourbonniere, Sandra Brovold, Lluis Camarero, Sudeep Chandra, Jim Cotner, Laura Forsstom, Guillaume Grosbois, Chris Harrod, Klaus D. Joehnk, T.Y. Kim, Daniel Langenhaun, Reet Laugaste, Suzanne McGowan, Virginia Panizzo, Giampaolo Rossetti, R.E.H. Smith, Sarah Spaulding, Helen Tammert, Steve Thackeray, Kyle Zimmer, Priit Zingel and two anonymous reviewers. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the US Government.

Tennessee is one of the 26 lead state partners that volunteered to provide leadership and guidance to states for the purpose of adoption of Next Generation Science Standards (NGSS. As stated in the Tennessee Vision for STEM Education (2009), "Tennessee recognizes the importance of science and aims to commit to this understanding by becoming involved in the development, and eventual adoption and implementation of NGSS." The present study correlates the Tennessee State Science Standards to the NGSS for High School Biology/ Life Sciences and examines the need for a dynamic set of standards that teach the technical skills and critical thinking needed in these scientific fields. The NGSS addresses a move from dated scientific quandaries and proposes standards supported by cutting edge scientific research and literature. Partnerships between scientists and educators allow for the information exchange necessary to implement the changes in scientific research in K-12 instruction. Professional development opportunities that include direct partnerships with scientists foster the continued understanding and skills required to teach science., 35 pages (including 5 figures) followed by 19 pages of Guidemaps

The Framework for K-12 Science Education (July 2011) developed by the National Resource Council (NRC) draws on current scientific research and the ways students learn science effectively. This laid the foundation for Next Generation Science Standards (NGSS) released in Spring 2013. Tennessee was one of the 26 lead state partners to provide leadership to the standards writing team and to provide guidance as states deliberate on the adoption and implementation of the NGSS. We propose that the transition from current State science standards to NGSS demonstrates a extensive consensus on what all students should know and be able to do at specific K-12 grade levels and what topics can be postponed or excluded on the premise of developmental readiness. In order to facilitate this work, one of the STEM Fellows, Larry Bowman (author), created a series of 18 posters showing correlations between the current Tennessee Science Education standards (Huffman, 2009) and NGSS (Achieve, 2013). This article specifically addresses the NGSS Middle Grades Disciplinary Core Ideas (DCIs) as compared to the existing 6-8 Science Standards from the Tennessee Science Curriculum Framework. Some Grade Level Expectations (GLEs) for Middle Grades Science have been relocated to other grade levels, and others have been introduced. The term Middle Grades is used for students 10 to 15 years of age covering the critical years when children are transitioning from concrete operational to formal operational stages. (Piaget and Inhelder 2013)., 9 pages, 3 Figures