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In July 2021, Computer Science (CS) standards were officially added as a subject area within the K-12 Montana content standards. However, due to a lack of professional development and pre-service preparation in CS, schools and teachers in Montana are underprepared to implement these standards. Montana is also a unique state, since AmericanIndian education is mandated by the state constitution in what is known as the IndianEducation for All Act. We are developing elementary and middle school units and teacher training materials that simultaneously address CS, Indian Education, and other Montana content standards. In this paper, we present a unit for fourth through sixth grades using a participatory design approach. Through physical computing, students create a visual narrative of their own stories inspired by ledger art, an American Indian art medium for recording lived experiences. We discuss the affordances and challenges of an integrated approach to CS teaching and learning in elementary and middle schools in Montana. 

A spatiotemporal optical vortex (STOV) is an intrinsic optical orbital angular momentum (OAM) structure in which the OAM vector is orthogonal to the propagation direction [Optica6,1547(2019)OPTIC82334-253610.1364/OPTICA.6.001547] and the optical phase circulates in space-time. Here, we experimentally and theoretically demonstrate the generation of the second harmonic of a STOV-carrying pulse along with the conservation of STOV-based OAM. Our experiments verify that photons can have intrinsic orbital angular momentum perpendicular to their propagation direction.

 

We present a technique for the single-shot measurement of the spatiotemporal (1D$\mathrm{s}\mathrm{p}\mathrm{a}\mathrm{c}\mathrm{e}+\mathrm{t}\mathrm{i}\mathrm{m}\mathrm{e}$) amplitude and phase of an ultrashort laser pulse. The method, transient grating single-shot supercontinuum spectral interferometry (TG-SSSI), is demonstrated by the space–time imaging of short pulses carrying spatiotemporal optical vortices. TG-SSSI is well suited for characterizing ultrashort laser pulses that contain singularities associated with spin/orbital angular momentum or polarization.