Several parks, attractions, and museums in Beijing have reverted back to their usual Monday closures. Details are as follows:
Temple of Heaven Park

[Photo via VCG]
Starting from September 1, the ancient architectural complexes, including the Hall of Prayer for Good Harvests, Echo Wall, Circular Mound Altar, Fasting Palace, Divine Kitchen (North) (北神厨), and Animal Sacrifice Pavilion (North) (北宰牲亭), have resumed Monday closures (except for statutory holidays).
Inquiry hotline: +86-10-67028866
Fragrant Hills Park

[Photo via VCG]
The Xiangshan Temple (香山寺) and Biyun Temple (碧云寺) in the park have resumed Monday closures starting from September 1 (except for statutory holidays).
Inquiry hotline: +86-10-62591222
Beihai Park

[Photo via VCG]
Starting from September 1, the following scenic areas in Beihai Park have resumed Monday closures: the Temple of Eternal Peace (永安寺), Hall of Ripples (漪澜堂), Painted Boat Studio (画舫斋), Tranquil Heart Studio (静心斋), Western Heaven Temple (西天梵境), Temple of Expounding Blessings (阐福寺), and Relic Site of Ten-Thousand-Buddha Tower (万佛楼).
Opening hours: 8:00–18:00 from Tuesday to Sunday (last entry at 17:30)
Inquiry hotline: +86-10-64037972
Zizhuyuan Park (Purple Bamboo Park)

[Photo via VCG]
The imperial palace complex (行宫), Mountain Retreat of Friends of Virtue (友贤山馆), and the exhibition space of Moon Inquiry Hall (问月楼) have resumed Monday closures starting from September 1 (except for statutory holidays).
Grand Canal Museum of Beijing (Capital Museum East Branch)

[Photo via Beijing Daily]
Starting from September 1, the museum has resumed Monday closures (except for statutory holidays). Arrangements for special circumstances will be announced separately.
Inquiry hotlines: +86-10-60583388, +86-10-88121227 (10:00–20:00, Monday to Sunday)
Miaoying Temple (White Stupa Temple)

[Photo via Beijing Daily]
Starting from August 31 (Monday), the temple has resumed Monday closures and regular opening hours. Extended evening hours on Fridays and Saturdays have been discontinued.
Opening hours: 9:00–17:00 (last ticket sales and entry at 16:30)
Beijing Auto Museum

[Photo via tuchong.com]
Starting from September 7, the museum will resume Monday closures. Arrangements for special circumstances will be announced separately. Regular opening hours from Tuesday to Sunday are from 9:00 to 17:00, with ticket sales ending at 16:00 and last entry at 16:30.
Inquiry hotline: +86-10-63756666
Report and supervision hotlines: +86-10-63856286, +86-10-63756666
Beijing Ancient Architecture Museum

[Photo via Beijing Daily]
Starting from September 7 (Monday), the museum will resume Monday closures. Extended evening hours on Saturdays will be discontinued.
Opening hours: 9:00–17:00, Tuesday to Sunday (last ticket sales and entry at 16:30)
China National Film Museum

[Photo via tuchong.com]
Starting from August 31 (Monday), the museum has ended its summer staggered schedule and resumed Monday closures. Regular opening hours are in effect from Tuesday to Sunday.
To meet the needs of film enthusiasts, on the closure day of September 7 (Monday), the IMAX theater will host four screenings of "The Odyssey". For specific showtimes, please check the "Recent Screenings" (近期影讯) section on the official WeChat account of the China National Film Museum (中国电影博物馆).
China National Botanical Garden

[Photo via Beijing Daily]
Starting from September 7, the following areas will resume Monday closures (except for statutory holidays):
North Garden: Exhibition Greenhouse, Low-temperature Greenhouse, Popular Science Exhibition Center, Cao Xueqin Memorial Hall, Temple of Reclining Buddha, and Bonsai Garden
South Garden: Greenhouse
Hotline: +86-10-82598771
(Source: Beijing Daily)