Among other things, the present disclosure provides technologies for altering splicing, particularly for increasing inclusion of exons in splicing products. In some embodiments, the present disclosure provides SMN2 oligonucleotides, compositions, and methods thereof. In some embodiments, the present disclosure provides chirally controlled SMN2 oligonucleotide compositions. In some embodiments, provided oligonucleotides and compositions can increase level of an exon 7-containing SMN2 splicing product and/or a gene product thereof. In some embodiments, the present disclosure provides methods for treatment of splicing-related conditions, disorders and diseases. In some embodiments, the present disclosure provides methods for treating SMN2-related conditions, disorders and diseases such as SMA (spinal muscular atrophy) and ALS (amyotrophic lateral sclerosis).