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The importance of fault tolerance continues to increase for HPC applications. The continued growth in size and complexity of HPC systems, and of the applications them- selves, is leading to an increased likelihood of failures during execution. However, most HPC programming models do not have a built-in fault tolerance mechanism. Instead, application developers usually rely on external support such as application- level checkpoint-restart (C/R) libraries to make their codes fault tolerant. However, this increases the burden on the application developer, who must use the libraries carefully to ensure correct behavior and to minimize the overheads. The C/R routines will be employed to save the values of all needed program variables at the places in the code where they are invoked. It is important for correctness that the program data is in a consistent state at these places. It is non-trivial to determine such points in OpenSHMEM, which relies upon single-sided communications to provide high performance. The amount of data to be collected, and the frequency with which this is performed, must also be carefully tuned, as the overheads introduced by C/R calls can be extremely high. There is very little prior work on checkpoint-restart support in the context of the OpenSHMEM programming interface. In this paper, we introduce OpenSHMEM and describe the challenges it poses for checkpointing. We identify the safest places for inserting C/R calls in an OpenSHMEM program and describe a straightforward approach for identifying the data that needs to be checkpointed at these positions in the code. We provide these two functionalities in a tool that exploits compiler analyses to propose checkpoints and the sets of data for saving at them, to the application developer. 

We provide an example from our integrated math and science curriculum where students explore the mathematical relationships underlying various science phenomena. We present the tasks we designed for exploring the covariation relationships that underlie the concept of gravity and discuss the generalizations students made as they interacted with those tasks. 

We designed an instructional module that seamlessly integrates mathematics, environmental science, and technology to help students think critically about climate change. The results from a design experiment in a sixth-grade classroom show that our tasks not only enhanced students' covariational reasoning in mathematics but also helped students identify the different traits of climate change they encounter every day in the news media. 

This paper discusses our work in progress aiming to explore how computer simulations can be integrated into the K-12 curriculum of Earth and Environmental science. Several interactive simulations using Netlogo, a multi-agent modeling environment, and Scratch, a visual programming software are being developed with steerable parameters and the corresponding output plots for students to manipulate and interpret the results, respectively. Here, we present two simulations we designed on water cycle and discuss how these may help students learn about the distribution of water and its continuous move in the ecosystem.